CN113764456B - LED chip light source and preparation method thereof - Google Patents

Abstract

The present invention provides an LED chip light source and a preparation method thereof. After forming an LED wafer, the LED wafer is bonded to a flexible wiring wafer by using a wafer-level bonding process, so that the LED functional layer of the LED wafer is bonded to the second surface of the flexible wiring wafer, and then the substrate of the LED wafer is removed and a scribe groove is formed in the LED functional layer to define a single chip area; the flexible wiring wafer can be cut into a predetermined shape and size along the scribe groove to form a plurality of LED chip light sources including at least one chip area, and the cut flexible wiring wafer constitutes a flexible substrate of the LED chip light source, so that each of the LED chip light sources is flexible and easy to bend and fold, avoiding the problems of high defective rate, low efficiency, high rework rate and high cost caused by transferring the prepared LED chip to a flexible circuit substrate, so that the preparation of flexible display screens using Mini/Micro LED chips has mass production feasibility.

Description

LED chip light source and preparation method thereof

Technical Field

The present invention relates to the field of semiconductor manufacturing technology, and in particular to an LED chip light source and a manufacturing method thereof.

Background technique

Currently, the only light source that can be used for mass production of flexible display screens is OLED (Organic Light-Emitting Diode), which has the following main disadvantages: 1) low brightness, low power, and the screen cannot be made very large; 2) large light decay, easy screen burn-in, and short life; 3) high investment cost and expensive price; 4) high technical threshold, currently only in the hands of a few manufacturers such as Samsung.

On the other hand, the concept of using Mini/Micro LED chips to make display screens (non-flexible display screens) is very popular, but it is difficult to achieve mass production. The reason is that the chip area is too small. To make a complete display screen, it takes a lot of time to transfer a large number of Mini/Micro LED chips to the circuit substrate for packaging. At present, the efficiency of mass chip transfer is very low, and the transfer position is easy to shift, resulting in high defective rate, high repair rate and high cost. The equipment and machine capabilities cannot meet the required accuracy, and it is basically not feasible to mass produce. If you want to use Mini/Micro LED chips to make flexible display screens, you need to transfer a large number of Mini/Micro LED chips to flexible circuit substrates. Because flexible circuit substrates are easy to deform and difficult to fix, it is even more difficult to make flexible display screens.

Summary of the invention

The purpose of the present invention is to provide an LED chip light source and a method for preparing the same, so as to solve the problem that it is currently difficult to mass-produce flexible display screens using Mini/Micro LEDs.

In order to achieve the above object, the present invention provides a method for preparing an LED chip light source, comprising:

Providing a substrate, forming an LED functional layer on the substrate, wherein the substrate and the LED functional layer constitute an LED wafer;

Bonding the LED wafer to a flexible wiring wafer, and laminating the LED functional layer to the second surface of the flexible wiring wafer;

removing the substrate and forming scribe lines in the LED functional layer to define individual chip regions; and,

The flexible wiring wafer is cut into a predetermined shape and size along the scribe line to form a plurality of LED chip light sources including at least one chip area. The cut flexible wiring wafer constitutes a flexible substrate of the LED chip light source.

Optionally, the number of chip areas included in the LED chip light source is the same or different.

Optionally, the shapes of the LED chip light sources are the same or different.

Optionally, the sizes of the LED chip light sources are the same or different.

Optionally, the LED functional layer is an LED functional layer of a flip-chip structure, and the LED chip light source is an LED chip light source of a flip-chip structure.

Optionally, the LED functional layer of the flip-chip structure includes an epitaxial layer, a groove, a reflector layer and a plurality of electrode groups; and the steps of forming the LED functional layer of the flip-chip structure on the substrate include:

forming the epitaxial layer on the substrate, wherein the epitaxial layer comprises a first semiconductor layer, a light emitting layer and a second semiconductor layer which are sequentially arranged on the substrate;

Etching the epitaxial layer to form the groove, wherein the groove extends from the first surface of the second semiconductor layer into the first semiconductor layer;

forming the reflector layer on a portion of the first surface of the second semiconductor layer; and,

The electrode groups are formed on the reflector layer, and each of the electrode groups includes two electrodes insulated from each other, and the two electrodes are electrically connected to the first semiconductor layer and the second semiconductor layer respectively.

Optionally, the LED functional layer of the flip-chip structure further includes a first insulating layer and a first opening; after forming the groove and before forming the reflector layer, the step of forming the LED functional layer of the flip-chip structure further includes:

forming the first insulating layer on the second semiconductor layer and the inner wall of the groove, wherein the first insulating layer has the first opening, a portion of the first opening exposes a portion of the first semiconductor layer at the bottom of the groove, and another portion of the first opening exposes a portion of the second semiconductor layer; and

When forming the reflector layer, the reflector layer is formed in the first opening that exposes a portion of the second semiconductor layer.

Optionally, the LED functional layer of the flip-chip structure further includes a current spreading layer and a connecting metal layer; after forming the reflector layer and before forming the electrode group, the step of forming the LED functional layer of the flip-chip structure further includes:

forming the current spreading layer on the reflector layer, wherein the current spreading layer is electrically connected to the second semiconductor layer through the reflector layer;

forming the connection metal layer on the current spreading layer and in the groove, the connection metal layer being electrically connected to the first semiconductor layer, and the connection metal layer and the current spreading layer being electrically isolated from each other; and

One of the two electrodes is electrically connected to the second semiconductor layer through the current spreading layer, and the other is electrically connected to the first semiconductor layer through the connecting metal layer.

Optionally, the LED functional layer of the flip-chip structure further includes a second insulating layer and a second opening; after forming the current spreading layer and before forming the connecting metal layer, the step of forming the LED functional layer of the flip-chip structure further includes:

forming the second insulating layer on the first insulating layer and the current spreading layer, wherein the second insulating layer has the second opening, a portion of the second opening is connected to a portion of the first opening to expose a portion of the first semiconductor layer, and another portion of the second opening exposes a portion of the current spreading layer; and

When forming the connection metal layer, the connection metal layer is formed on the second insulating layer and fills the connected first opening and the second opening.

Optionally, the LED functional layer of the flip-chip structure further includes a third insulating layer and a third opening; after forming the connecting metal layer and before forming the electrode group, the step of forming the LED functional layer of the flip-chip structure further includes:

The third insulating layer is formed on the second insulating layer and the connecting metal layer. The third insulating layer has the third opening. A part of the third opening is connected with a part of the second opening to expose a part of the current spreading layer, and another part of the third opening exposes a part of the connecting metal layer.

Optionally, both electrodes are formed on the third insulating layer, and one electrode fills the connected second opening and the third opening to be electrically connected to the current spreading layer; the other electrode fills the remaining third opening to be electrically connected to the connecting metal layer.

Optionally, the first semiconductor layer is etched to form the scribe groove penetrating the first semiconductor layer, and before the flexible wiring wafer is cut along the scribe groove, the flexible wiring wafer is bent so that the first insulating layer, the second insulating layer and the third insulating layer are broken at the scribe groove.

Optionally, the LED functional layer of the flip-chip structure includes an epitaxial layer, a groove, an insulating reflective layer and a plurality of electrode groups; the steps of forming the LED functional layer of the flip-chip structure on the substrate include:

forming the epitaxial layer on the substrate, wherein the epitaxial layer comprises a first semiconductor layer, a light emitting layer and a second semiconductor layer which are sequentially arranged on the substrate;

Etching the epitaxial layer to form the groove, wherein the groove extends from the first surface of the second semiconductor layer into the first semiconductor layer;

forming the insulating reflective layer on the second semiconductor layer, wherein the insulating reflective layer fills the groove; and

The electrode groups are formed on the insulating reflective layer, each of the electrode groups includes two mutually insulated electrodes, and the two electrodes pass through the insulating reflective layer and are electrically connected to the first semiconductor layer and the second semiconductor layer respectively.

Optionally, the LED functional layer of the flip-chip structure further includes two first metal layers; before forming the insulating reflective layer on the second semiconductor layer, the step of forming the LED functional layer of the flip-chip structure further includes:

forming one first layer of metal on the first semiconductor layer and the second semiconductor layer at the bottom of the groove, respectively, and the two first layers of metal are electrically connected to the first semiconductor layer and the second semiconductor layer, respectively; and

After the electrode group is formed on the insulating reflective layer, the two electrodes pass through the insulating reflective layer and are electrically connected to one of the first metal layers respectively.

Optionally, the LED functional layer of the flip-chip structure further includes a current blocking layer and a current spreading layer; before forming the first metal layer, the step of forming the LED functional layer of the flip-chip structure further includes:

forming the current blocking layer on a portion of the first surface of the second semiconductor layer; and

The current spreading layer is formed on at least a portion of the first surface of the second semiconductor layer and the current blocking layer.

Optionally, the first semiconductor layer is etched to form the scribe groove penetrating the first semiconductor layer, and before the flexible wiring wafer is cut along the scribe groove, the flexible wiring wafer is bent so that the insulating reflective layer is broken at the scribe groove.

Optionally, the LED functional layer is a vertically structured LED functional layer, and the LED chip light source is a vertically structured LED chip light source.

Optionally, the vertically structured LED functional layer comprises an epitaxial layer, a reflector layer, two insulating protective layers and a plurality of electrode groups; and the steps of forming the vertically structured LED functional layer on the substrate comprise:

forming the epitaxial layer on the substrate, wherein the epitaxial layer comprises a first semiconductor layer, a light emitting layer and a second semiconductor layer which are sequentially arranged on the substrate;

forming the reflector layer on a portion of the first surface of the second semiconductor layer;

forming a first insulating protection layer on the second semiconductor layer and the reflector layer;

forming one electrode in the electrode group on the first insulating protective layer, wherein the one electrode passes through the first insulating protective layer and is electrically connected to the second semiconductor layer;

After forming the scribe groove in the LED functional layer, forming a second insulating protection layer on the first semiconductor layer and the second surface of the flexible wiring wafer; and,

Another electrode in the electrode group is formed on the second insulating protective layer, one end of the other electrode passes through the second insulating protective layer to be electrically connected to the first semiconductor layer, and the other end extends into the scribe groove and passes through the second insulating protective layer at the bottom of the scribe groove to be electrically connected to the flexible wiring wafer.

Optionally, the vertical structure LED functional layer further includes a metal protective layer; after forming the reflector layer and before forming the first insulating protective layer, the step of forming the vertical structure LED functional layer further includes:

The metal protection layer is formed on at least a portion of the first surface of the second semiconductor layer and the reflector layer.

Optionally, the epitaxial layer and the first insulating protective layer are etched to form the scribe groove penetrating the epitaxial layer and the first insulating protective layer; or, the epitaxial layer is etched to form the scribe groove penetrating the epitaxial layer, and then the first insulating protective layer is bent to break the first insulating protective layer at the scribe groove; and,

Before cutting the flexible wiring wafer along the scribe line, the flexible wiring wafer is bent so that the second insulating protection layer is broken at the scribe line.

Optionally, the materials of the electrodes are all bonding metal materials, and the LED wafer is bonded to the flexible wiring wafer using all the electrodes.

Optionally, the bonding metal material includes at least two of gold, tin, nickel, silver and copper.

Optionally, before bonding the LED wafer to the flexible wiring wafer, the method further includes:

fixing the flexible wiring wafer on a supporting wafer; and,

Before cutting the flexible wiring wafer, the flexible wiring wafer is separated from the supporting wafer.

Optionally, the step of fixing the flexible wiring wafer on the supporting wafer includes:

An adhesive layer is formed on the support wafer, and the flexible wiring wafer is fixed on the support wafer through the adhesive layer; when the material of the adhesive layer is a metal material, a grinding process is used to remove the support wafer and the adhesive layer to separate the flexible wiring wafer from the support wafer; when the material of the adhesive layer is an organic adhesive material, an organic cleaning solvent is used to decompose the adhesive layer to separate the flexible wiring wafer from the support wafer.

Optionally, the thickness of the supporting wafer is greater than or equal to 250 μm.

Optionally, the supporting wafer is a silicon-containing wafer or a sapphire wafer.

Optionally, the second surface of the flexible wiring wafer has a metal wiring layer, the first surface of the flexible wiring wafer is fixed on the supporting wafer, and the LED functional layer is bonded to the second surface of the flexible wiring wafer.

Optionally, the metal wiring layer includes a plurality of wiring areas, each of which has at least one metal wire. After the LED wafer is bonded to the flexible wiring wafer, one chip area is aligned with one wiring area, and the electrodes corresponding to each chip area are electrically connected to the metal wires of the corresponding wiring area.

Optionally, the material of the flexible wiring wafer is flexible glass, silicone or epoxy resin or a flexible high molecular polymer containing silicon oxide.

Optionally, the substrate is removed by a laser lift-off process or a grinding process.

Optionally, after removing the substrate, the method further includes:

The second surface of the first semiconductor layer of the LED functional layer is roughened using an alkaline solution.

The present invention also provides an LED chip light source, comprising:

a flexible substrate having a predetermined shape and size; and,

The LED functional layer has an electrode surface. The LED functional layer is located on the flexible substrate and the electrode surface is attached to the flexible substrate. The LED functional layer includes at least one chip area.

Optionally, the LED chip light source is an LED chip light source with a flip-chip structure, and the LED functional layer is an LED functional layer with a flip-chip structure.

Optionally, the LED functional layer of the flip-chip structure includes:

The epitaxial layer includes a first semiconductor layer, a light emitting layer and a second semiconductor layer arranged in sequence from top to bottom;

a groove located in the epitaxial layer and extending from the first surface of the second semiconductor layer into the first semiconductor layer;

a reflector layer formed on the first surface of the second semiconductor layer and covering a portion of the second semiconductor layer; and

The electrode group is formed on the first surface of the reflector layer, and includes two electrodes insulated from each other. The two electrodes are electrically connected to the first semiconductor layer and the second semiconductor layer respectively, and the first surface of the electrode is the electrode surface.

Optionally, the LED functional layer of the flip-chip structure further includes:

a current spreading layer, formed on the first surface of the reflector layer and electrically connected to the second semiconductor layer through the reflector layer;

a connecting metal layer, formed on the first surface of the current spreading layer and filling the groove to be electrically connected to the first semiconductor layer, the connecting metal layer and the current spreading layer being electrically isolated from each other; and

One of the two electrodes is electrically connected to the second semiconductor layer through the current spreading layer, and the other is electrically connected to the first semiconductor layer through the connecting metal layer.

Optionally, the LED functional layer of the flip-chip structure further includes:

A first insulating layer is formed on the first surface of the second semiconductor layer and covers the inner wall of the groove. The first insulating layer has a first opening. A portion of the first opening exposes a portion of the first semiconductor layer at the bottom of the groove, and another portion of the first opening exposes a portion of the second semiconductor layer. The reflector layer is located in the first opening that exposes a portion of the second semiconductor layer.

Optionally, the LED functional layer of the flip-chip structure further includes:

A second insulating layer is formed on the first surface of the first insulating layer and the current spreading layer to electrically isolate the current spreading layer from the connecting metal layer, wherein the second insulating layer has a second opening, a portion of the second opening is connected to a portion of the first opening to expose a portion of the first semiconductor layer, and another portion of the second opening exposes a portion of the current spreading layer.

Optionally, the connecting metal layer is formed on the first surface of the second insulating layer and fills the connected first opening and the second opening to be electrically connected to the first semiconductor layer.

Optionally, the LED functional layer of the flip-chip structure further includes:

A third insulating layer is formed on the first surface of the second insulating layer and the connecting metal layer to electrically isolate the two electrodes, wherein the third insulating layer has a third opening, a portion of the third opening is connected to a portion of the second opening to expose a portion of the current spreading layer, and another portion of the third opening exposes a portion of the connecting metal layer.

Optionally, both electrodes are located on the first surface of the third insulating layer, and one electrode fills the connected second opening and the third opening to be electrically connected to the current spreading layer; the other electrode fills the remaining third opening to be electrically connected to the connecting metal layer.

Optionally, the LED functional layer of the flip-chip structure includes:

An epitaxial layer, wherein the epitaxial layer comprises a first semiconductor layer, a light-emitting layer and a second semiconductor layer arranged in sequence from top to bottom;

a groove extending from the first surface of the second semiconductor layer into the first semiconductor layer;

an insulating reflective layer, formed on the first surface of the second semiconductor layer and filling the groove; and

An electrode group is formed on the first surface of the insulating reflective layer, each of the electrode groups includes two electrodes insulated from each other, both of the two electrodes pass through the insulating reflective layer and are electrically connected to the first semiconductor layer and the second semiconductor layer respectively, and the first surface of the electrode is the electrode surface.

Optionally, the LED functional layer of the flip-chip structure further includes:

Two first metal layers are respectively formed on the first semiconductor layer at the bottom of the groove and the first surface of the second semiconductor layer, and the two first metal layers are respectively electrically connected to the first semiconductor layer and the second semiconductor layer; and

The two electrodes both pass through the insulating reflective layer and are electrically connected to one of the first metal layers respectively.

Optionally, the LED functional layer of the flip-chip structure further includes:

a current blocking layer formed on a portion of the first surface of the second semiconductor layer; and

A current spreading layer is formed on at least a portion of the first surface of the second semiconductor layer and the first surface of the current blocking layer.

Optionally, the LED chip light source is a vertically structured LED chip light source, and the LED functional layer is a vertically structured LED functional layer.

Optionally, the vertically structured LED functional layer includes:

The epitaxial layer includes a first semiconductor layer, a light emitting layer and a second semiconductor layer arranged in sequence from top to bottom;

a reflector layer formed on a portion of the first surface of the second semiconductor layer;

Two insulating protective layers, wherein a first insulating protective layer is formed on the second semiconductor layer and the first surface of the reflector layer, and a second insulating protective layer is formed on the second surface of the first semiconductor layer and the exposed second surface of the flexible wiring wafer;

A plurality of electrode groups, wherein one electrode in the electrode group is formed on the first surface of the first insulating protective layer and is electrically connected to the second semiconductor layer through the first insulating protective layer, another electrode in the electrode group is formed on the second surface of the second insulating protective layer, and two ends thereof are electrically connected to the first semiconductor layer and the flexible wiring wafer respectively through the second insulating protective layer, and the first surfaces of the one electrode and the other electrode are the electrode surfaces.

Optionally, the vertically structured LED functional layer further includes:

A metal protection layer is formed on at least a portion of the first surface of the second semiconductor layer and the first surface of the reflector layer.

Optionally, the second surface of the flexible substrate has a metal wiring layer, and the electrode surface is attached to the second surface of the flexible substrate.

Optionally, the metal wiring layer includes at least one wiring area, each wiring area has at least one metal wire, one chip area is aligned with one wiring area, and electrodes corresponding to each chip area are electrically connected to the metal wires of the corresponding wiring area.

Optionally, the material of the flexible substrate is flexible glass, silica gel or epoxy resin or a flexible high molecular polymer containing silicon oxide.

In the LED chip light source and the preparation method thereof provided by the present invention, after forming an LED wafer, the LED wafer is bonded to a flexible wiring wafer by using a wafer-level bonding process, so that the LED functional layer of the LED wafer is bonded to the second surface of the flexible wiring wafer, and then the substrate of the LED wafer is removed and a scribe groove is formed in the LED functional layer to define a single chip area; the flexible wiring wafer can be cut into a predetermined shape and size along the scribe groove to form a plurality of LED chip light sources including at least one chip area, and LED chip light sources of various shapes and sizes can be prepared. The cut flexible wiring wafer constitutes a flexible substrate of the LED chip light source, so that each of the LED chip light sources is flexible and easy to bend and fold, avoiding the problems of high defective rate, low efficiency, high rework rate and high cost caused by transferring the prepared LED chip to the flexible circuit substrate, so that the preparation of flexible display screens using Mini/Micro LED chips has mass production feasibility.

Furthermore, the brightness per unit area of the flexible LED chip light source provided by the present invention is several times higher than that of OLED, and can be made into large-size screens. It has the advantages of extremely low light decay, no screen burn-in, long life and low cost.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a flow chart of a method for preparing an LED chip light source provided in Embodiment 1 of the present invention;

2 to 18 are schematic structural diagrams of corresponding steps of a method for preparing a flip-chip LED chip light source provided in Embodiment 1 of the present invention;

19 to 29 are schematic structural diagrams of corresponding steps of a method for preparing a flip-chip LED chip light source according to a second embodiment of the present invention;

30 to 39 are schematic structural diagrams of corresponding steps of a method for preparing a vertically structured LED chip light source provided in Embodiment 3 of the present invention;

Wherein, the accompanying drawings are marked as follows:

100-substrate; 200-epitaxial layer; 201-first semiconductor layer; 202-light emitting layer; 203-second semiconductor layer; 200a-groove; 300-current blocking layer; 301-first insulating layer; 302-second insulating layer; 303-third insulating layer; 304-first insulating protection layer; 305-second insulating protection layer; 400, 405-reflector layer; 401-insulating reflective layer; 403-fourth opening; 404-fifth opening; 406-metal protection layer; 500-current spreading layer; 501-current spreading layer; 502-connecting metal layer; 503-first layer of N metal; 504-first layer of P metal; 60-chip area; 600-electrode; 601-first electrode; 602-second electrode; 700-slice groove; 80-wiring area; 801-first metal line; 802-second metal line;

001-support wafer; 002-flexible wiring wafer; 012-flexible substrate; 003-adhesive layer; 004-LED wafer.

Detailed ways

The specific embodiments of the present invention will be described in more detail below in conjunction with the schematic diagrams. The advantages and features of the present invention will become more apparent from the following description. It should be noted that the drawings are all in a very simplified form and are not in exact proportions, and are only used to conveniently and clearly assist in explaining the purpose of the embodiments of the present invention.

Embodiment 1

Fig. 18 is a schematic diagram of the structure of the LED chip light source provided in this embodiment. As shown in Fig. 18, the LED chip light source includes a flexible substrate 012 and an LED functional layer, the flexible substrate 012 has a predetermined shape and size, the LED functional layer is located on the flexible substrate 012, and the LED functional layer includes at least one chip area.

Please refer to Figure 15. In this embodiment, the LED functional layer only includes one chip area 60, but it is not limited to this. In other embodiments, the LED functional layer can also include multiple chip areas 60. In this way, the LED chip light source can be of any possible shape and size, and has a very wide range of applications.

Furthermore, the second surface of the flexible substrate 012 has a metal wiring layer, and the LED functional layer is bonded to the second surface of the flexible substrate 012, which is equivalent to bonding the LED functional layer to the metal wiring layer. The metal wiring layer includes at least one wiring area 80, each of which has at least one metal wire, one chip area 60 is aligned with one wiring area 80, and the electrodes corresponding to each chip area 60 are electrically connected to the metal wires of the corresponding wiring area 80.

In this embodiment, the wiring area 80 has two metal wires, namely the first metal wire 801 and the second metal wire 802. The chip area 60 corresponds to two electrodes, namely the first electrode 601 and the second electrode 602. The first electrode 601 is electrically connected to the first metal wire 801, and the second electrode 602 is electrically connected to the second metal wire 802.

Furthermore, the material of the flexible substrate 012 is flexible glass, silicone or epoxy resin or a flexible high molecular polymer containing silicon oxide, so that the LED chip light source is flexible and easy to bend and fold.

Specifically, in this embodiment, the LED chip light source is an LED chip light source with a flip-chip structure, and the LED functional layer is an LED functional layer with a flip-chip structure.

Please refer to Figure 10, the LED functional layer of the flip-chip structure includes an epitaxial layer 200, a groove 200a, a reflector layer 400, a current spreading layer 501, a connecting metal layer 502, a first insulating layer 301, a second insulating layer 301, a third insulating layer 303, a first opening, a second opening, a third opening and an electrode group.

Specifically, the epitaxial layer 200 includes a first semiconductor layer 201, a light-emitting layer 202, and a second semiconductor layer 203 arranged in sequence from bottom to top. In this embodiment, the first semiconductor layer 201 in the epitaxial layer 200 is an N-type semiconductor layer, and the material of the first semiconductor layer 201 is N-GaN; the light-emitting layer 202 is a multi-period quantum well layer (MQWS), and the material of the quantum well layer is any one or a combination of AlN, GaN, AlGaN, InGaN, and AlInGaN; the second semiconductor layer 203 is a P-type semiconductor layer, and the material of the second semiconductor layer 203 is P-GaN.

In this embodiment, the total thickness of the epitaxial layer 200 is 5 μm to 10 μm.

Furthermore, the groove 200a is located in the epitaxial layer 200, and the groove 200a passes through the light-emitting layer 202 from the first surface of the second semiconductor layer 203 and extends into the first semiconductor layer 201. The groove 200a constitutes a MESA step, and the upper step surface of the MESA step is the second semiconductor layer 203, and the lower step surface is the first semiconductor layer 201. The upper step surface and the lower step surface are connected to form a MESA step side surface.

Please continue to refer to FIG. 10 , the first insulating layer 301 covers the sidewalls and part of the bottom surface of the groove 200a, and also extends laterally to cover part of the first surface of the second semiconductor layer 203, that is, the first insulating layer 301 covers the side surface of the MESA step, part of the upper step surface and part of the lower step surface, exposing part of the first semiconductor layer 201 and part of the second semiconductor layer 203. Alternatively, it can be understood that the first insulating layer 301 covers the second semiconductor layer 203 and the inner wall of the groove 200a, and a plurality of first openings are formed in the first insulating layer 301, a portion of the first openings are located in the groove 200a to expose part of the first semiconductor layer 201 at the bottom of the groove 200a, and another portion of the first openings are located on the second semiconductor layer 203 to expose part of the second semiconductor layer 203.

In this embodiment, the thickness of the first insulating layer 301 is 10nm-10μm. The material of the first insulating layer 301 includes at least one of silicon oxide, silicon nitride and DBR. The function of the first insulating layer 301 is to protect the side of the MESA step in advance, so as to prevent the side of the MESA step from being contaminated by long-term exposure to the air, thereby avoiding the failure of the turn-on voltage VFin and/or the leakage current IR.

The reflector layer 400 is formed on the first surface of the second semiconductor layer 203 and is located in the first opening that exposes a portion of the second semiconductor layer 203. The reflector layer 400 covers the first surface of the second semiconductor layer 203 exposed by the first opening, so that the reflector layer 400 can be electrically connected to the second semiconductor layer 203. The reflector layer 400 has a light-reflecting effect and can reflect back the portion of light emitted by the light-emitting layer 202 that is directed toward the second semiconductor layer 203. The reflector layer 400 includes one or more of silver (Ag), aluminum (Al) and ITO. In this embodiment, the reflector layer 400 is a silver layer.

In this embodiment, the thickness of the reflector layer 400 is 100nm~2μm, and the reflector layer 400 has a spacing of 0um~6um from the side of the MESA step, that is, the reflector layer 400 has a lateral spacing of 0um~6um from the side of the MESA step. Compared with the large spacing between the reflector layer 400 and the side of the MESA step in the prior art, since the first insulating layer 301 is pre-set in this embodiment, there is no need to consider the contamination problem of the MESA step, so the distance between the reflector layer 400 and the side of the MESA step can be greatly reduced, that is, the area of the reflector layer 400 of the present application can be made larger, and then the reflection effect will be better.

The current spreading layer 501 is formed on the first surface of the reflector layer 400, covers the first surface of the reflector layer 400 and part of the first insulating layer 301, and is electrically connected to the second semiconductor layer 203 through the reflector layer 400. The current spreading layer 501 serves as a P-layer current spreading layer. In this embodiment, the current spreading layer 501 completely covers the reflector layer 400, thereby protecting the reflector layer 400 and preventing leakage caused by electron migration. The material of the current spreading layer 501 includes one or more of titanium (Ti), platinum (Pt), aluminum (Al), nickel (Ni), chromium (Cr) and gold (Au). In addition to protecting the reflector layer 400, the current spreading layer 501 also has the function of spreading the current over the entire surface, so there is a requirement for its thickness. If it is too thin, the current spreading is not good. Preferably, the thickness of the current spreading layer 501 is 0.5μm to 3μm.

As an optional embodiment, the current spreading layer 501 may also be located only on the first surface of the reflector layer 400 and cover the first surface of the reflector layer 400, and the first surface of the first insulating layer 301 may not have the current spreading layer 501.

The second insulating layer 302 is located on the first surface of the first insulating layer 301 and the current spreading layer 501. Alternatively, it can be understood that the second insulating layer 302 covers the current spreading layer 501 and extends into the groove 200a to cover the first surface of the first insulating layer 301. The second insulating layer 302 has a plurality of second openings, a portion of the second openings is located in the groove 200a and communicates with the first opening in the groove 200a to expose a portion of the first semiconductor layer 201 at the bottom of the groove 200a, and another portion of the second openings is located on the first surface of the current spreading layer 501 to expose the portion of the current spreading layer 501.

In this embodiment, the thickness of the second insulating layer 302 is 10nm-10μm. The material of the second insulating layer 302 includes at least one of silicon oxide, silicon nitride and DBR. Since the first insulating layer 301 protects the side of the MESA step in advance, the second insulating layer 302 serves to insulate and protect the current spreading layer 501.

The connection metal layer 502 is located on the first surface of the second insulating layer 302. The connection metal layer 502 covers a portion of the first surface of the second insulating layer 302 and fills the connected first opening and the second opening, and covers the portion of the first semiconductor layer 201 exposed by the first opening and the second opening. It should be understood that the connection metal layer 502 is equivalent to filling the groove 200a, so as to be electrically connected to the first semiconductor layer 201.

In this embodiment, the material of the connection metal layer 502 includes one or more of titanium (Ti), platinum (Pt), aluminum (Al), nickel (Ni), chromium (Cr) and gold (Au). Similarly, the connection metal layer 502 has the function of spreading the current over the entire surface, so there is a requirement for its thickness. If it is too thin, the current will not spread well. Preferably, the thickness of the connection metal layer 502 is 0.5μm to 3μm.

The third insulating layer 303 is located on the first surface of the connection metal layer 502 and the second insulating layer 302. The third insulating layer 303 has a plurality of third openings, a portion of the third openings are connected to the second openings that expose a portion of the current spreading layer 501, and another portion of the third openings expose a portion of the connection metal layer 502. The third insulating layer 303 can electrically isolate the connection metal layer 502 from the second electrode 602 formed subsequently, to prevent a short circuit between the connection metal layer 502 used to spread the N current and the second electrode 602 used to input the P current, and at the same time, the third insulating layer 303 can also protect the side and a portion of the surface of the device.

In this embodiment, the thickness of the third insulating layer 303 is 10 nm to 10 μm, and the material of the third insulating layer 303 includes at least one of silicon oxide, silicon nitride and DBR.

The electrode group includes a first electrode 601 and a second electrode 602, and the first electrode 601 and the second electrode 602 are both located on the first surface of the third insulating layer 303. The first electrode 601 covers a portion of the first surface of the third insulating layer 303 and fills the third opening exposing the connecting metal layer 502, and the second electrode 602 covers a portion of the first surface of the third insulating layer 303 and fills the connected third opening and the second opening. In this way, the first electrode 601 can be electrically connected to the first semiconductor layer 201 through the connecting metal layer 502, and the second electrode 602 can be electrically connected to the second semiconductor layer 203 through the current spreading layer 501.

The first electrode 601 and the second electrode 602 are electrically isolated from each other by a certain distance. In this embodiment, the distance between the first electrode 601 and the second electrode 602 is 10 μm to 300 μm.

In this embodiment, the thickness of the first electrode 601 and the second electrode 602 is 0.1 μm to 10 μm. In this embodiment, the materials of the first electrode 601 and the second electrode 602 are both bonding metal materials, so as to facilitate the subsequent bonding process. The bonding metal material can be composed of at least two metals of gold (Au), tin (Sn), nickel (Ni), silver (Ag) and copper (Cu). For example, the bonding metal material can be AuSn, NiSn or SnAgCu.

As can be seen from FIG. 18 , the first surfaces of the first electrode 601 and the second electrode 602 serve as electrode surfaces of the LED functional layer and are bonded to the second surface of the flexible wiring wafer 002.

FIG1 is a flow chart of a method for preparing an LED chip light source provided in this embodiment. As shown in FIG1 , the method for preparing an LED chip light source includes:

Step S100: providing a substrate, forming an LED functional layer on the substrate, wherein the substrate and the LED functional layer constitute an LED wafer;

Step S200: bonding the LED wafer to a flexible wiring wafer, and laminating the LED functional layer to the second surface of the flexible wiring wafer;

Step S300: removing the substrate and forming a scribe groove in the LED functional layer to define a single chip area; and

Step S400: cutting the flexible wiring wafer into a predetermined shape and size along the scribe line to form a plurality of LED chip light sources including at least one chip area, and the cut flexible wiring wafer constitutes a flexible substrate of the LED chip light source.

In this embodiment, the LED chip light source is a flip-chip LED chip light source, and Figures 2 to 18 show the structural schematic diagrams of the corresponding steps of the method for preparing the flip-chip LED chip light source provided by this embodiment. Next, the method for preparing the LED chip light source provided by this embodiment will be described in detail by taking the flip-chip LED chip light source as an example in combination with Figures 2 to 18.

Referring to FIG. 2 , step S100 is performed to provide a substrate 100 and form an LED functional layer on the substrate 100 .

In this embodiment, the substrate 100 is a high-transmittance sapphire substrate (Al ₂ O ₃ ). As an optional embodiment, the substrate 100 may also be a substrate such as silicon (Si), silicon carbide (SiC), gallium nitride (GaN) or zinc oxide (ZnO). Further, the substrate 100 is a patterned substrate (Patterned Sapphire Substrates, PSS), such as a micron-scale/nanoscale patterned sapphire substrate. The LED functional layer of the flip-chip structure is formed on the substrate 100 .

First, please continue to refer to FIG. 2 . An epitaxial layer 200 is formed on the substrate 100 . The epitaxial layer 200 includes a first semiconductor layer 201 , a light emitting layer 202 , and a second semiconductor layer 203 arranged in sequence from bottom to top.

The epitaxial layer 200 is formed by, for example, etching a pattern on the substrate 100 using a standard photolithography process, and then etching the substrate 100 using an ICP etching technique to pattern the substrate 100 to improve the light-emitting efficiency. Further, the epitaxial layer 200 can be formed on the substrate 100 by any epitaxial technique such as metal chemical vapor deposition, laser-assisted molecular beam epitaxy, hydride vapor phase epitaxy, evaporation, etc., and the epitaxial layer 200 can be a polycrystalline structure or a single crystal structure.

Referring to FIG. 3 , the epitaxial layer 200 is partially etched at periodic intervals to form periodic grooves 200a. The grooves 200a penetrate the second semiconductor layer 203 and the light emitting layer 202 and extend into the first semiconductor layer 201.

Specifically, the steps of forming the groove 200a include: making a light-emitting area MESA pattern through a photolithography process, etching the epitaxial layer 200 with ICP (inductively coupled plasma etching equipment) to form the groove 200a, the etching depth needs to exceed the light-emitting layer 202, and expose the first semiconductor layer 201, and from the side view, a platform (MESA) is etched to form a MESA step.

In this embodiment, there are one or more grooves 200a, and the grooves 200a may have a periodic interval, and the periodic interval is, for example, 10μm to 300μm, the depth of the groove 200a is 1μm to 2μm, and the width of the groove 200a is 20μm to 100μm.

Please refer to Fig. 4, a first insulating layer 301 is formed on the side surface, part of the upper step surface and part of the lower step surface of the MESA step. The specific steps of forming the first insulating layer 301 may be: forming a first insulating material layer (not shown in Fig. 4) by PECVD (Plasma Enhanced Chemical Vapor Deposition), then making a mask with a positive photoresist, etching the first insulating material layer with ICP (Inductively Coupled Plasma Etching Equipment) or corroding the first insulating material layer with a BOE solution or an HF solution to form a plurality of first openings, a part of the first openings exposes a part of the first semiconductor layer 201, another part of the first openings exposes a part of the second semiconductor layer 203, and the remaining first insulating material layer constitutes the first insulating layer 301.

Referring to Fig. 5, a reflector layer 400 is formed on the second semiconductor layer 203. The steps of forming the reflector layer 400 include: forming a mask pattern by a negative photolithography process, growing a reflector film with a high reflectivity by processes such as electron beam evaporation, sputtering, and ALD (Atomic layer deposition), and finally removing the mask and the reflector film on the mask by a lift-off method, and the remaining reflector film constitutes the reflector layer 400. It should be understood that the reflector layer 400 needs to completely expose the groove 200a.

As an optional embodiment, the reflector layer 400 may form a good ohmic contact with the second semiconductor layer 203 by high temperature annealing in a N ₂ atmosphere.

Referring to Fig. 6, a current spreading layer 501 is formed on the reflector layer 400. The steps of forming the current spreading layer 501 may be: forming a mask pattern by a negative resist photolithography process, then growing a current spreading film by electron beam evaporation, sputtering, ALD, etc., and finally removing the mask and the current spreading film on the mask by a gold stripping and resist stripping process, and the remaining current spreading film constitutes the current spreading layer 501.

Referring to Fig. 7, a second insulating layer 302 is formed on the first insulating layer 301 and the current spreading layer 501. The steps of forming the second insulating layer 302 may be: forming a second insulating material layer (not shown in Fig. 7) by PECVD, then making a mask by using a positive photoresist, etching the second insulating material layer by using an ICP (inductively coupled plasma etching device) or etching the second insulating material layer by using a BOE solution or an HF solution, to form a portion of a second opening, wherein the second opening formed at this time is connected to the first opening in the groove to expose a portion of the first semiconductor layer 201 at the bottom of the groove 200a.

8, a connection metal layer 502 is formed on the second insulating layer 302. The steps of forming the connection metal layer 502 may be: forming a mask pattern by a negative resist photolithography process, then growing a current spreading film by electron beam evaporation, sputtering, ALD, etc., and finally removing the mask and the current spreading film on the mask by a gold stripping and resist stripping process, and the remaining current spreading film forms the connection metal layer 502.

Please refer to FIG. 9 , a third insulating layer 303 is formed on the connection metal layer 502. The third insulating layer 303 is preferably formed by PECVD to form a third insulating material layer, and then a positive photoresist is used to make a mask, and the third insulating material layer and a part of the film layer below it are etched by ICP (inductive plasma coupled etching equipment) or the third insulating layer 303 material layer is corroded by BOE solution or HF solution to form a third opening, and at this time, the third opening only exposes the connection metal layer 502. Then, it is necessary to etch the second insulating layer 302 at the bottom of a part of the third opening to form a second opening in the second insulating layer 302 again, and the second opening formed at this time is connected to the third opening above it. Finally, the remaining third insulating material layer constitutes the third insulating layer 303, and the remaining second insulating material layer constitutes the second insulating layer 302.

Referring to Fig. 10, a plurality of electrode groups are formed on the third insulating layer 303, each of which includes a first electrode 601 and a second electrode 602. The steps of forming the first electrode 601 and the second electrode 602 may be: forming a mask pattern by a negative resist photolithography process, then growing a conductive metal film by electron beam evaporation, sputtering, ALD and other processes, and finally removing the mask and the conductive metal film on the mask by a gold stripping and resist removal process, and the remaining conductive metal film constitutes the first electrode 601 and the second electrode 602.

Please refer to Fig. 11, after the LED functional layer is formed, the LED functional layer and the substrate 100 together constitute the LED wafer 004. The LED wafer 004 has a plurality of chip areas 60 distributed in an array, each of which is used to form one LED chip, and one chip area 60 corresponds to one electrode group.

Referring to FIG. 12 , step S200 is performed to provide a flexible wiring wafer 002. The flexible wiring wafer 002 is designed with a metal wiring layer (not shown) as required. In this embodiment, the metal wiring layer is located on the second surface of the flexible wiring wafer 002, but the present invention is not limited thereto. Furthermore, the metal wiring layer has a plurality of wiring areas 80 distributed in an array, and each of the wiring areas 80 corresponds to a chip area 60.

Furthermore, the flexible wiring wafer 002 is prepared using a flexible substrate, so that the flexible wiring wafer 002 is flexible. Therefore, the material of the flexible substrate can be a flexible material, such as flexible glass, silicone, epoxy resin or other flexible polymers (such as flexible polymers containing silicon oxide). Optionally, the material of the flexible substrate can also be a high-temperature resistant material to avoid being damaged in the subsequent preparation process, such as high-temperature resistant flexible glass, high-temperature resistant silicone, high-temperature resistant epoxy resin or other high-temperature resistant flexible polymers.

Referring to Fig. 13, a support wafer 001 is provided, and the flexible wiring wafer 002 is fixed on the support wafer 001. Since the second surface of the flexible wiring wafer 002 has the metal wiring layer, the first surface of the flexible wiring wafer 002 is fixed to the support wafer 001 to expose the metal wiring layer on the second surface of the flexible wiring wafer 002. Each wiring area 80 of the metal wiring layer has a first metal wire 801 and a second metal wire 802, which are respectively used to electrically connect with the first electrode 601 and the second electrode 602 of the corresponding chip area 60 and transfer charges for the corresponding LED chip.

The supporting wafer 001 provides support for the flexible wiring wafer 002 in the subsequent preparation process. Therefore, the supporting wafer 001 can be a silicon wafer or a sapphire wafer or other wafer that can provide support.

Further, in this embodiment, the flexible wiring wafer 002 is fixed on the supporting wafer 001 through an adhesive layer 003, and the adhesive layer 003 is used to bond the flexible wiring wafer 002 to the supporting wafer 001. In this embodiment, the material of the adhesive layer 003 is a metal material, and a metal material layer can be first formed on the supporting wafer 001, and then the flexible wiring wafer 002 is pressed onto the metal material layer by pressure, so as to fix the flexible wiring wafer 002 on the supporting wafer 001; or, a metal solution can be dotted or coated on the supporting wafer 001, and the flexible wiring wafer 002 is placed on the supporting wafer 001, and the metal solution is solidified to form the adhesive layer 003, so as to achieve the fixing of the flexible wiring wafer 002 and the supporting wafer 001.

As an optional embodiment, the material of the adhesive layer 003 can also be an organic adhesive material such as photoresist. The organic adhesive is coated on the supporting wafer 001, and the flexible wiring wafer 002 is placed on the supporting wafer 001. After the organic adhesive is cured, the flexible wiring wafer 002 and the supporting wafer 001 can be fixed.

Optionally, in order to ensure that the supporting wafer 001 has good supporting performance, in this embodiment, the thickness of the supporting wafer 001 is greater than or equal to 250 μm.

Referring to FIG. 14 , the LED wafer 004 is bonded to the flexible wiring wafer 002, and the electrode surface of the LED functional layer is bonded to the second surface of the flexible wiring wafer 002. That is, the LED wafer 004 is flipped over and bonded to the flexible wiring wafer 002, and the first surfaces of the first electrode 601 and the second electrode 602 are bonded to the metal wiring layer of the flexible wiring wafer 002. Since the first electrode 601 and the second electrode 602 are both made of bonding metal material, the LED wafer 004 can be bonded to the flexible wiring wafer 002 by using all of the first electrodes 601 and the second electrodes 602.

Please refer to Figure 15. When the LED wafer 004 is bonded to the flexible wiring wafer 002, one of the chip areas 60 is aligned with one of the wiring areas 80. The first electrode 601 and the second electrode 602 in the chip area 60 respectively contact the first metal wire 801 and the second metal wire 802 of the corresponding wiring area 80. The first electrode 601 is electrically connected to the first metal wire 801, and the second electrode 602 is electrically connected to the second metal wire 802.

It should be understood that the substrate 100 in this embodiment is a transparent substrate. When the LED wafer 004 is bonded to the flexible wiring wafer 002, the alignment mark on the flexible wiring wafer 002 can be seen through the substrate 100, so that the LED wafer 004 can be accurately aligned with the flexible wiring wafer 002.

Please refer to FIG. 16 , and execute step S300 to remove the substrate 100 by laser lift-off process or grinding process, and roughen the first semiconductor layer 201 of the LED functional layer by alkaline solution to increase light extraction efficiency.

It should be understood that the alkaline solution can be a solvent such as sodium hydroxide (NaOH) or potassium hydroxide (KOH).

Referring to Fig. 17, the first semiconductor layer 201 is etched to form a through-going scribe groove 700 in the first semiconductor layer 201. The scribe groove 700 is crisscrossed on the first semiconductor layer 201 and completely disconnects the first semiconductor layer 201. The rectangular areas divided by the scribe groove 700 are the individual chip areas 60, that is, the scribe groove 700 separates each chip area 60, so the scribe groove 700 can define the individual chip areas 60.

It should be understood that when etching the first semiconductor layer 201 to form the scribe groove 700, an etchant that is larger than the etching selectivity of the first insulating layer 301, the second insulating layer 302 and the third insulating layer 303 can be selected to prevent the first insulating layer 301, the second insulating layer 302 and the third insulating layer 303 from being etched together when etching the first semiconductor layer 201, thereby damaging the metal wiring layer of the flexible wiring wafer 002, thereby causing the conduction performance of the chip to decrease.

Referring to Fig. 18, step S400 is performed to separate the flexible wiring wafer 002 from the supporting wafer 001. In this embodiment, since the material of the adhesive layer 003 is a metal material, a grinding process is used to remove the supporting wafer 001 and the adhesive layer 003, thereby separating the flexible wiring wafer 002 from the supporting wafer 001.

As an optional embodiment, when the material of the adhesive layer 003 is an organic adhesive material, an organic cleaning solvent can be used to decompose the adhesive layer 003, thereby separating the flexible wiring wafer 002 from the supporting wafer 001.

Next, the flexible wiring wafer 002 is bent. Since the first insulating layer 301, the second insulating layer 302 and the third insulating layer 301 are all made of insulating materials and are relatively brittle, when the flexible wiring wafer 002 is bent, the first insulating layer 301, the second insulating layer 302 and the third insulating layer 301 are broken at the scribe groove 700, so that the chip area 60 of the LED wafer 004 is completely separated. Next, the flexible wiring wafer 002 is cut into a predetermined shape and size along the scribe line 700 to form a plurality of LED chip light sources including at least one chip area, which is equivalent to being able to form the LED chip light source of any shape and size, and has a wide applicability; and the cut flexible wiring wafer 002 constitutes a flexible substrate 012 of the LED chip light source, so that each of the LED chip light sources is flexible and easy to bend and fold, thereby avoiding the problems of high defective rate, low efficiency, high rework rate and high cost caused by transferring the prepared LED chip to the flexible circuit substrate, so that the use of Mini/Micro LED chips to prepare flexible display screens has the feasibility of mass production.

Embodiment 2

The difference from the first embodiment is that in this embodiment, the LED chip light source is another LED chip light source with a flip-chip structure, and the LED functional layer is also another LED functional layer with a flip-chip structure.

Please refer to FIG. 26 , the LED functional layer includes an epitaxial layer 200 , a groove 200 a , a current blocking layer 300 , a current spreading layer 500 , two first metal layers, an insulating reflective layer 401 and an electrode group.

Specifically, in this embodiment, the epitaxial layer 200 is formed on the first surface of the substrate 100, and the epitaxial layer 200 includes a first semiconductor layer 201, a light emitting layer 202, and a second semiconductor layer 203 arranged in sequence from bottom to top.

The groove 200a is located at the edge of the epitaxial layer 200, and the groove 200a extends from the first surface of the second semiconductor layer 203 through the light emitting layer 202 and then extends into the first semiconductor layer 201.

Please continue to refer to FIG. 26 , the current blocking layer 300 and the current spreading layer 500 are both formed on the first surface of the second semiconductor layer 203, the current blocking layer 300 covers a portion of the first surface of the second semiconductor layer 203, and the current blocking layer 300 has a good current guiding effect. The width of the current spreading layer 500 in the direction perpendicular to the thickness is greater than the width of the current blocking layer 300, so that the current spreading layer 500 not only covers a portion of the first surface of the second semiconductor layer 203, but also completely covers the current blocking layer 300, thereby facilitating the lateral expansion of the current.

In this embodiment, the current blocking layer 300 and the current spreading layer 500 are both transparent film layers, so as not to cause adverse effects on light extraction efficiency and light extraction intensity. The material of the current blocking layer 300 can be silicon oxide, silicon nitride, titanium oxide, aluminum oxide or perovskite electronic ceramic (ABO ₃ ), etc.; the current spreading layer 500 is made of materials such as ITO or AZO. In this embodiment, the current blocking layer 300 is a single-layer silicon oxide layer, and the material of the current spreading layer 500 is ITO.

Please continue to refer to FIG. 26 , the two first metal layers are respectively a first N metal layer 503 and a first P metal layer 504, and the first N metal layer 503 and the first P metal layer 504 are respectively formed in the groove 200a and formed on the first surface of the current spreading layer 500. The first N metal layer 503 is located at the bottom of the groove 200a and is electrically connected to the first semiconductor layer 201, and in a direction perpendicular to the thickness, the width of the first N metal layer 503 is smaller than the width of the groove 200a, and there is a gap between the first N metal layer 503 and the sidewall of the groove 200a, so as to achieve electrical insulation between the first N metal layer 503 and the first P metal layer 504; the first P metal layer 504 is located on the current spreading layer 500, and is electrically connected to the second semiconductor layer 203 through the current spreading layer 500.

Furthermore, the first layer of P metal 504 corresponds to the position of the current blocking layer 300, and the area of the current blocking layer 300 is larger than the area of the first layer of P metal 504. The current blocking layer 300 can reduce the light loss caused by the first layer of P metal 504 absorbing/blocking light, and reduce the vertical transmission of current and increase the lateral transmission.

Further, the insulating reflective layer 401 covers the first surface of the second semiconductor layer 203 and fills the groove 200a. That is, the insulating reflective layer 401 covers the chip area on its entire surface, and the gap between the first layer of N metal 503 and the side wall of the groove 200a is also filled by the insulating reflective layer 401. In this way, the first layer of N metal 503 and the first layer of P metal 504 can be electrically insulated by the insulating reflective layer 401. At the same time, the insulating reflective layer 401 has a reflective effect and can act as a reflector to reflect back the part of the light emitted by the light-emitting layer 202 that is directed to the insulating reflective layer 401. The material of the insulating reflective layer 401 includes two or more of silicon oxide, titanium oxide, aluminum oxide or silicon nitride. In this embodiment, the insulating reflective layer 401 is formed by alternately evaporating at least two layers of high and low refractive index films, but is not limited thereto.

In this embodiment, the insulating reflective layer 401 can not only realize the electrical insulation between the first layer of N metal 503 and the first layer of P metal 504, but also act as a reflector. Moreover, since the insulating reflective layer 401 covers the entire surface, the area is larger and the reflective effect is better.

Please continue to refer to FIG. 26 , the electrode group includes two electrodes, the two electrodes are a first electrode 601 and a second electrode 602. The first electrode 601 penetrates the insulating reflective layer 401, and the second surface of the first electrode 601 contacts the first layer of N metal 503 to achieve electrical connection, so that the first electrode 601 can be electrically connected to the first semiconductor layer 201 through the first layer of N metal 503. Similarly, the second electrode 602 penetrates the insulating reflective layer 401, and the second surface of the second electrode 602 contacts the first layer of P metal 504 to achieve electrical connection, so that the second electrode 602 can be electrically connected to the second semiconductor layer 203 through the first layer of P metal 504 and the current spreading layer 500.

In this embodiment, the materials of the first electrode 601 and the second electrode 602 may be at least two metals selected from the group consisting of gold (Au), tin (Sn), nickel (Ni), silver (Ag) and copper (Cu).

As can be seen from FIG. 30 , the first surfaces of the first electrode 601 and the second electrode 602 serve as the electrode surfaces and are bonded to the second surface of the flexible wiring wafer 002.

Figures 19 to 29 show the structural schematic diagrams of the corresponding steps of the method for preparing the flip-chip structure LED chip light source provided by this embodiment. Next, the method for preparing the LED chip light source will be described in detail in conjunction with Figures 19 to 29.

Please refer to FIG. 19 , in step S100 , a substrate 100 is provided, and a flip-chip LED functional layer is formed on the substrate 100 .

Next, how to form the LED functional layer of the flip-chip structure will be described.

Please continue to refer to FIG. 19 , an epitaxial layer 200 is formed on the substrate 100 , and the epitaxial layer 200 includes a first semiconductor layer 201 , a light emitting layer 202 , and a second semiconductor layer 203 arranged in sequence from bottom to top.

The substrate 100 and the epitaxial layer 200 are formed by, for example, etching a pattern on the substrate 100 using a standard photolithography process, and then etching the substrate 100 using an ICP (inductively coupled plasma etching device) to pattern the substrate 100 to improve the light-emitting efficiency. Further, the epitaxial layer 200 can be formed on the substrate 100 by any epitaxial technology such as metal chemical vapor deposition, laser-assisted molecular beam epitaxy, hydride vapor phase epitaxy, evaporation, etc., and the epitaxial layer 200 can be a polycrystalline structure or a single crystal structure.

Please refer to FIG. 20 , the epitaxial layer 200 is partially etched to form a groove 200a, and the groove 200a penetrates the second semiconductor layer 203 and the light emitting layer 202 and extends into the first semiconductor layer 201. Specifically, the steps of forming the groove 200a include: using a photolithography process to make a light emitting area MESA pattern, using ICP to etch the epitaxial layer 200 to form the groove 200a, the etching depth needs to exceed the light emitting layer 202, and the first semiconductor layer 201 is exposed, and a platform (MESA) is etched from the side to form a MESA step, and the MESA step includes an upper step surface and a lower step surface, wherein the upper step surface is the second semiconductor layer 203, the lower step surface is the first semiconductor layer 201, and the upper step surface and the lower step surface are connected to form the side of the MESA step.

Referring to FIG21 , a current blocking layer 300 is formed on the second semiconductor layer 203. The steps of forming the current blocking layer may be: a current blocking material is deposited on the entire surface through a deposition process (not shown in FIG21 ), a mask is then made using a photoresist, and then a portion of the current blocking material and the mask are removed through an etching process and a stripping process, so that a portion of the current blocking material on the second semiconductor layer 203 is retained, and the remaining current blocking material constitutes the current blocking layer 300.

Referring to FIG. 22 , a current spreading layer 500 is formed on the second semiconductor layer 203. The steps of forming the current spreading layer 500 include: depositing a current spreading material (not shown in FIG. 22 ) on the entire surface through a deposition process, then using a photoresist to make a mask, and then using an etching process and a stripping process to remove part of the current spreading material and the mask, so that part of the current spreading material on the second semiconductor layer 203 and all of the current spreading material on the current blocking layer 300 are retained, and the remaining current spreading material constitutes the current spreading layer 500.

Referring to Fig. 23, two first layers of metal are formed on the groove 200a and the current spreading layer 500, respectively, and the two first layers of metal are respectively a first layer of N metal 503 and a first layer of P metal 504. The steps of forming the first layer of N metal 503 and the first layer of P metal 504 may be: forming a patterned photoresist layer on the current spreading layer 500, wherein the patterned photoresist layer defines a pattern for forming the first layer of N metal 503 and the first layer of P metal 504, then forming a first layer of electrode material by a process such as sputtering, finally stripping the patterned photoresist and removing the first layer of electrode material on the patterned photoresist at the same time, and the remaining first layer of electrode material can constitute the first layer of N metal 503 and the first layer of P metal 504.

Please refer to FIG. 24 , an insulating reflective layer 401 is fully deposited on the second semiconductor layer 203 , and the insulating reflective layer 401 fills the groove 200 a and extends to cover the second semiconductor layer 203 .

Referring to FIG. 25 , the insulating reflective layer 401 is etched to form a fourth opening 403 and a fifth opening 404. The fourth opening 403 and the fifth opening 404 penetrate the insulating reflective layer 401 and expose the first surface of the first layer of N metal 503 and the first layer of P metal 504, respectively.

Referring to Fig. 26, the fourth opening 403 and the fifth opening 404 are filled with conductive material, and the conductive material also extends to cover the first surface of the insulating reflective layer 401. Then, etching is performed to remove part of the conductive material on the first surface of the insulating reflective layer 401, and the conductive material in the fourth opening 403 and part of the conductive material on the first surface of the insulating reflective layer 401 constitute the first electrode 601, and the conductive material in the fifth opening 404 and the remaining conductive material on the first surface of the insulating reflective layer 401 constitute the second electrode 602, and the first electrode 601 and the second electrode 602 constitute an electrode group.

Referring to FIG. 27 , step S200 is performed to bond the LED wafer 004 composed of the substrate 100 and the flip-chip LED functional layer to the flexible wiring wafer 002, and the electrode surface of the LED functional layer is bonded to the second surface of the flexible wiring wafer 002. That is, after the LED wafer 004 is flipped over, the first surfaces of the first electrode 601 and the second electrode 602 are bonded to the metal wiring layer of the flexible wiring wafer 002.

Referring to FIG. 28 , step S300 is performed to remove the substrate 100 by using a laser lift-off process or a grinding process, and to roughen the first semiconductor layer 201 of the LED functional layer by using an alkaline solution to increase light extraction efficiency.

Referring to FIG. 29 , the first semiconductor layer 201 is etched to form a penetrating scribe line 700 in the first semiconductor layer 201 .

Please continue to refer to FIG. 29 , and execute step S400 to separate the flexible wiring wafer 002 from the supporting wafer 001 and remove the adhesive layer 003 .

Referring to Fig. 30, the flexible wiring wafer 002 is bent so that the insulating reflective layer 401 is broken at the scribe groove 700, so that the chip area of the LED wafer is completely separated. Next, the flexible wiring wafer 002 is cut into a predetermined shape and size along the scribe groove 700 to form a plurality of LED chip light sources including at least one chip area. The cut flexible wiring wafer 002 constitutes the flexible substrate 012 of the LED chip light source.

Embodiment 3

The difference from the first embodiment and the second embodiment is that in this embodiment, the LED chip light source is a vertically structured LED chip light source, and the LED functional layer is a vertically structured LED functional layer.

Fig. 39 is a schematic diagram of the structure of the LED chip light source provided in this embodiment, and Fig. 34 is a schematic diagram of the structure of part of the LED functional layer of the vertical structure provided in this embodiment. As shown in Fig. 34 and Fig. 39, in this embodiment, the LED functional layer of the vertical structure includes an epitaxial layer 200, a reflector layer 405, a metal protective layer 406, a first insulating protective layer 304, a second insulating protective layer 305 and an electrode group.

Please refer to Fig. 34, specifically, the reflector layer 405 is formed on the first surface of the epitaxial layer 200 and covers part of the first surface of the second semiconductor layer 203. The reflector layer 405 is used to reflect back the light emitted by the epitaxial layer 200 toward the flexible substrate 012. The reflector layer 405 is a reflector made of silver (Ag), platinum (Pt), tungsten (W), titanium (Ti), aluminum (Al), ITO, etc., and the thickness is usually 0.1um-2um.

Please continue to refer to Figures 34 and 39. The metal protection layer 406 is located on the epitaxial layer 200 and covers part of the first surface of the second semiconductor layer 203 and the first surface of the reflector layer 405. The metal protection layer 406 is used to protect the reflector layer 405 to prevent leakage caused by migration of materials in the reflector layer 405. The material of the metal protection layer 406 is one or more of metals such as Ti, Pt, Au, Al, Ni, Cr, etc., and the thickness is between 0.5um and 3um.

The first insulating protective layer 304 is formed on the first surface of the epitaxial layer 200, and covers the remaining first surface of the second semiconductor layer 203 and a portion of the first surface of the metal protective layer 406; the second insulating protective layer 305 is formed on the second surface of the first semiconductor layer 201, and covers the second surface of the first semiconductor layer 201 and the side of the epitaxial layer 200. At the same time, the second insulating protective layer 305 also covers the exposed second surface of the flexible wiring wafer 002.

The first insulating protection layer 304 and the second insulating protection layer 305 are both SiO ₂ layers, SiN _x layers, stacked layers of SiO ₂ /SiN _x , or DBR, etc., and the thickness of the first insulating protection layer 304 is 0.01 um-10 um.

As shown in FIG39 , the electrode group includes a first electrode 601 and a second electrode 602. The first electrode 601 is located on the second surface of the second insulating protective layer 305, one end of which passes through the second insulating protective layer 305 to be electrically connected to the first semiconductor layer 201, and the other end of which passes through the second insulating protective layer 305 to be electrically connected to the flexible wiring wafer 002; the second electrode 602 is formed on the first surface of the first insulating protective layer 304, passes through the first insulating protective layer 304 to contact the metal protective layer 406, and the second electrode 602 is electrically connected to the second semiconductor layer 203 through the metal protective layer 406 and the reflector layer 405.

The material of the first electrode 601 and the second electrode 602 can be AuSn, NiSn, SnAgCu or other metal materials that can be used for bonding. The thickness of the first electrode 601 and the second electrode 602 is 0.5um-10um.

As can be seen from FIG. 39 , the first surfaces of the first electrode 601 and the second electrode 602 serve as the electrode surfaces and are bonded to the second surface of the flexible wiring wafer 002.

Figures 31 to 39 are schematic diagrams of structures corresponding to corresponding steps of the method for preparing a vertical LED chip light source provided by this embodiment. Next, the method for preparing a vertical LED chip light source provided by this embodiment will be described in detail in conjunction with Figures 31 to 39.

Referring to FIG. 31 , step S100 is performed to provide the substrate 100 and form the epitaxial layer 200 on the substrate 100. The epitaxial layer 200 includes a first semiconductor layer 201, a light emitting layer 202 and a second semiconductor layer 203 which are sequentially arranged from bottom to top.

Referring to Fig. 32, a reflector layer 405 is formed on the epitaxial layer 200. The reflector layer 405 may be formed by forming a mask pattern through a negative photolithography process, growing a reflector film with a high reflectivity through processes such as electron beam evaporation, sputtering, and ALD (Atomic layer deposition), and finally removing the mask and the reflector film on the mask through a liftoff method, and the remaining reflector film constitutes the reflector layer 405.

Continuing to refer to FIG32, the metal protection layer 406 is formed on a portion of the first surface of the epitaxial layer 200 and the reflector layer 405. The method for forming the metal protection layer 406 may be: forming a mask pattern by a negative photolithography process, then growing a metal film by processes such as electron beam evaporation, sputtering, and ALD (Atomic layer deposition), and finally removing the mask and the metal film on the mask by a lift-off method, and the remaining metal film constitutes the metal protection layer 406.

Please refer to Figure 33. The first insulating protective layer 304 is formed on the remaining first surface of the epitaxial layer 200 and the metal protective layer 406. The first insulating protective layer 304 can isolate the epitaxial layer 200 and the metal protective layer 406 from the outside to protect the epitaxial layer 200 and the metal protective layer 406.

Therefore, after forming the first insulating protection layer 304, an etching process may be performed to remove a portion of the first insulating protection layer 304, so that at least a portion of the first surface of the metal protection layer 406 is exposed.

Referring to FIG. 34 , the second electrode 602 is formed on the first surface exposed by the metal protection layer 406, and the second electrode 602 is electrically connected to the second semiconductor layer 203 through the metal protection layer 406 and the reflector layer 405. In this embodiment, the second electrode 602 also extends to cover a portion of the first surface of the first insulating protection layer 304. The step of forming the second electrode 602 may be: preparing a metal material on the first surface exposed by the metal protection layer 406 by photolithography and electron beam evaporation process, thereby forming the second electrode 602.

Referring to FIG. 35 , step S200 is performed to bond the LED wafer consisting of the substrate 100 and the vertical LED functional layer to the flexible wiring wafer 002. That is, the LED wafer is flipped over and bonded to the flexible wiring wafer 002, and the first surface of the second electrode 602 is bonded to the metal wiring layer of the flexible wiring wafer 002.

Please refer to FIG. 36 , and execute step S300 to remove the substrate 100 by using a laser lift-off process or a grinding process, and roughen the first semiconductor layer 201 by using an alkaline solution to increase light extraction efficiency.

Please continue to refer to FIG. 36 , the entire epitaxial layer 200 is etched to form a scribe line 700 penetrating the epitaxial layer 200 , and then the flexible wiring wafer 002 is bent so that the first insulating protection layer 304 is broken at the scribe line 700 .

As an optional embodiment, the epitaxial layer 200 and the first insulating protective layer 304 may be etched step by step to form the scribe groove 700 penetrating the epitaxial layer 200 and the first insulating protective layer 304.

Please refer to Figure 37. A second insulating protective layer 305 is deposited on the entire surface. The second insulating protective layer 305 covers all exposed surfaces of the epitaxial layer 200, all exposed surfaces of the first insulating protective layer 304, and the second surface of the flexible wiring wafer 002.

Referring to FIG. 38 , the second insulating protective layer 305 is etched to form an opening exposing a portion of the second surface of the first semiconductor layer 201 and an opening exposing a portion of the second surface of the flexible wiring wafer 002, wherein the opening exposing a portion of the second surface of the first semiconductor layer 201 is located on the first semiconductor layer 201, and the opening exposing a portion of the second surface of the flexible wiring wafer 002 is located in the scribe line 700. Then, a first electrode 601 is formed on a portion of the second surface of the second insulating protective layer 305, and the first electrode 601 also fills the opening exposing a portion of the second surface of the first semiconductor layer 201 and the opening exposing a portion of the second surface of the flexible wiring wafer 002, so that the first electrode 601 can electrically connect the first semiconductor layer 201 with the metal wiring layer of the flexible wiring wafer 002.

Please refer to FIG. 39 , and execute step S400 to separate the flexible wiring wafer 002 from the supporting wafer 001 , and remove the adhesive layer 003 .

Please continue to refer to FIG. 39 , the flexible wiring wafer 002 is bent so that the second insulating protective layer 305 is broken at the scribe groove 700, so that the chip area of the LED wafer is completely separated. Next, the flexible wiring wafer 002 is cut into a predetermined shape and size along the broken part of the second insulating protective layer 305 to form a plurality of LED chip light sources including at least one chip area, and the cut flexible wiring wafer 002 constitutes the flexible substrate 012 of the LED chip light source.

The above embodiments are merely examples of several structures of the LED functional layer. It should be understood that the LED functional layer in the present invention is not limited thereto, and is applicable to all LED functional layers with inverted structures or vertical structures.

In summary, in the LED chip light source and the preparation method thereof provided in the present embodiment, after forming the LED wafer, the LED wafer is bonded to a flexible wiring wafer by using a wafer-level bonding process, so that the LED functional layer of the LED wafer is bonded to the second surface of the flexible wiring wafer, and then the substrate of the LED wafer is removed and a scribe groove is formed in the LED functional layer to define a single chip area; the flexible wiring wafer can be cut into a predetermined shape and size along the scribe groove to form a plurality of LED chip light sources including at least one chip area, and LED chip light sources of various shapes and sizes can be prepared. The cut flexible wiring wafer constitutes a flexible substrate of the LED chip light source, so that each of the LED chip light sources is flexible and easy to bend and fold, avoiding the problems of high defective rate, low efficiency, high rework rate and high cost caused by transferring the prepared LED chip to the flexible circuit substrate, so that the preparation of flexible display screens using Mini/MicroLED chips has mass production feasibility. Furthermore, the brightness per unit area of the flexible LED chip light source provided by the present invention is several times higher than that of OLED, and can be made into large-size screens. It has the advantages of extremely low light decay, no screen burn-in, long life and low cost.

The above are only preferred embodiments of the present invention and do not limit the present invention in any way. Any person skilled in the art may make any equivalent replacement or modification to the technical solution and technical content disclosed in the present invention without departing from the scope of the technical solution of the present invention, which shall be deemed as the content of the technical solution of the present invention and still fall within the protection scope of the present invention.

Claims (45)

1. The preparation method of the LED chip light source is characterized by comprising the following steps of:

providing a substrate, forming an LED functional layer on the substrate, wherein the substrate and the LED functional layer form an LED wafer;

bonding the LED wafer to a flexible wiring wafer, and attaching the LED functional layer to a second surface of the flexible wiring wafer;

removing the substrate and forming a scribing groove in the LED functional layer to define a single chip area; the method comprises the steps of,

cutting the flexible wiring wafer into a preset shape and size along the scribing groove to form a plurality of LED chip light sources comprising at least one chip area, wherein the cut flexible wiring wafer forms a flexible substrate of the LED chip light sources;

The second surface of the flexible wiring wafer is provided with a metal wiring layer, the metal wiring layer comprises a plurality of wiring areas, at least one metal wire is arranged in each wiring area, after the LED wafer is bonded to the flexible wiring wafer, one chip area is aligned to one wiring area, and electrodes corresponding to each chip area are respectively and electrically connected with the metal wires of the corresponding wiring area;

the LED functional layer comprises a plurality of electrode groups, each electrode group comprises two mutually insulated electrodes, the two electrodes are respectively and electrically connected with the first semiconductor layer and the second semiconductor layer of the LED functional layer, the materials of the electrodes are all bond metal materials, and all the electrodes are utilized to bond the LED wafer to the flexible wiring wafer.

2. The method of manufacturing an LED chip light source of claim 1, wherein the number of the chip regions included in the LED chip light source is the same or different.

3. The method of manufacturing a LED chip light source of claim 1, wherein the LED chip light sources are identical or different in shape.

4. The method of manufacturing a LED chip light source of claim 1, wherein the LED chip light sources are the same or different in size.

5. The method for manufacturing an LED chip light source according to claim 1, wherein the LED functional layer is an LED functional layer of a flip-chip structure, and the LED chip light source is an LED chip light source of a flip-chip structure.

6. The method of manufacturing a light source of an LED chip of claim 5, wherein the functional layer of the LED in flip-chip configuration comprises an epitaxial layer, a recess, and a reflector layer; the step of forming the LED functional layer of the flip-chip structure on the substrate comprises the following steps:

forming the epitaxial layer on the substrate, wherein the epitaxial layer comprises a first semiconductor layer, a light-emitting layer and a second semiconductor layer which are sequentially arranged on the substrate;

etching the epitaxial layer to form the recess extending from the first surface of the second semiconductor layer into the first semiconductor layer;

forming the mirror layer on a portion of the first surface of the second semiconductor layer; the method comprises the steps of,

the electrode group is formed on the mirror layer.

7. The method of manufacturing a light source of an LED chip of claim 6, wherein the functional layer of an LED in flip-chip configuration further comprises a first insulating layer and a first opening; after forming the grooves and before forming the reflector layer, the step of forming the LED functional layer of the flip-chip structure further comprises:

Forming a first insulating layer on the second semiconductor layer and on the inner wall of the groove, wherein the first insulating layer is provided with a first opening, one part of the first opening exposes part of the first semiconductor layer at the bottom of the groove, and the other part of the first opening exposes part of the second semiconductor layer; the method comprises the steps of,

the mirror layer is formed in the first opening exposing a portion of the second semiconductor layer when the mirror layer is formed.

8. The method of manufacturing a light source of an LED chip of claim 7, wherein the LED functional layer of the flip-chip structure further comprises a current spreading layer and a connection metal layer; after forming the reflector layer and before forming the electrode group, the step of forming the LED functional layer of the flip-chip structure further includes:

forming the current spreading layer on the reflector layer, wherein the current spreading layer is electrically connected with the second semiconductor layer through the reflector layer;

forming the connection metal layer on the current expansion layer and in the groove, wherein the connection metal layer is electrically connected with the first semiconductor layer, and the connection metal layer and the current expansion layer are electrically isolated from each other; the method comprises the steps of,

One of the two electrodes is electrically connected with the second semiconductor layer through the current expansion layer, and the other electrode is electrically connected with the first semiconductor layer through the connecting metal layer.

9. The method of manufacturing a light source of an LED chip of claim 8, wherein the LED functional layer of the flip-chip structure further comprises a second insulating layer and a second opening; after the current expansion layer is formed, before the connection metal layer is formed, the step of forming the LED functional layer of the flip-chip structure further comprises:

forming the second insulating layer on the first insulating layer and the current expansion layer, wherein the second insulating layer is provided with the second opening, a part of the second opening is communicated with a part of the first opening to expose a part of the first semiconductor layer, and the other part of the second opening exposes a part of the current expansion layer; the method comprises the steps of,

and when the connecting metal layer is formed, forming the connecting metal layer on the second insulating layer and filling the communicated first opening and the communicated second opening.

10. The method of manufacturing a light source of an LED chip of claim 9, wherein the functional layer of an LED in flip-chip configuration further comprises a third insulating layer and a third opening; after forming the connection metal layer and before forming the electrode group, the step of forming the LED functional layer of the flip-chip structure further includes:

And forming a third insulating layer on the second insulating layer and the connecting metal layer, wherein the third insulating layer is provided with a third opening, one part of the third opening is communicated with one part of the second opening to expose part of the current expansion layer, and the other part of the third opening exposes part of the connecting metal layer.

11. The method of claim 10, wherein two electrodes are formed on the third insulating layer, and one electrode fills the second opening and the third opening, which are connected to each other, so as to be electrically connected to the current spreading layer; the other electrode fills the rest of the third opening so as to be electrically connected with the connecting metal layer.

12. The method of manufacturing a LED chip light source of claim 11, wherein the first semiconductor layer is etched to form the scribe line penetrating the first semiconductor layer, and the flexible wiring wafer is bent to fracture the first, second and third insulating layers from the scribe line before cutting the flexible wiring wafer along the scribe line.

13. The method of manufacturing a light source of an LED chip of claim 5, wherein the functional layer of the LED in flip-chip configuration comprises an epitaxial layer, a recess, and an insulating reflective layer; the step of forming the LED functional layer of the flip-chip structure on the substrate comprises the following steps:

Forming the epitaxial layer on the substrate, wherein the epitaxial layer comprises a first semiconductor layer, a light-emitting layer and a second semiconductor layer which are sequentially arranged on the substrate;

etching the epitaxial layer to form the recess extending from the first surface of the second semiconductor layer into the first semiconductor layer;

forming the insulating reflection layer on the second semiconductor layer, wherein the groove is filled with the insulating reflection layer; the method comprises the steps of,

the electrode groups are formed on the insulating reflecting layer, and two electrodes of each electrode group penetrate through the insulating reflecting layer and are respectively and electrically connected with the first semiconductor layer and the second semiconductor layer.

14. The method of manufacturing a LED chip light source of claim 13, wherein the flip-chip LED functional layer further comprises two first layers of metal; the step of forming the LED functional layer of the flip-chip structure before forming the insulating reflective layer on the second semiconductor layer further includes:

forming a first layer of metal on the first semiconductor layer and the second semiconductor layer at the bottom of the groove respectively, wherein the two first layers of metal are electrically connected with the first semiconductor layer and the second semiconductor layer respectively; the method comprises the steps of,

After the electrode group is formed on the insulating reflecting layer, both the electrodes pass through the insulating reflecting layer and are electrically connected with one first layer metal respectively.

15. The method of manufacturing a light source of an LED chip of claim 14, wherein the LED functional layer of the flip-chip structure further comprises a current blocking layer and a current spreading layer; the step of forming the LED functional layer of the flip-chip structure further includes, before forming the first metal layer:

forming the current blocking layer on a portion of the first surface of the second semiconductor layer; and

the current spreading layer is formed on at least part of the first surface of the second semiconductor layer and the current blocking layer.

16. The method of manufacturing a LED chip light source of claim 13, wherein the first semiconductor layer is etched to form the scribe line through the first semiconductor layer, and the flexible wiring wafer is bent to fracture the insulating reflective layer from the scribe line before the flexible wiring wafer is cut along the scribe line.

17. The method for manufacturing an LED chip light source according to claim 1, wherein the LED functional layer is a LED functional layer of a vertical structure, and the LED chip light source is an LED chip light source of a vertical structure.

18. The method of manufacturing a LED chip light source of claim 17, wherein the LED functional layer of vertical structure comprises an epitaxial layer, a reflector layer and two insulating protective layers; the step of forming the LED functional layer of the vertical structure on the substrate comprises the following steps:

forming the epitaxial layer on the substrate, wherein the epitaxial layer comprises a first semiconductor layer, a light-emitting layer and a second semiconductor layer which are sequentially arranged on the substrate;

forming the mirror layer on a portion of the first surface of the second semiconductor layer;

forming a first insulating protection layer on the second semiconductor layer and on the mirror layer;

forming one electrode of the electrode group on the first insulating protection layer, wherein the one electrode penetrates through the first insulating protection layer and is electrically connected with the second semiconductor layer;

forming a second insulating protection layer on the first semiconductor layer and the second surface of the flexible wiring wafer after forming the scribe line in the LED functional layer; the method comprises the steps of,

and forming another electrode in the electrode group on the second insulating protection layer, wherein one end of the other electrode penetrates through the second insulating protection layer to be electrically connected with the first semiconductor layer, and the other end of the other electrode extends into the scribing groove and penetrates through the second insulating protection layer at the bottom of the scribing groove to be electrically connected with the flexible wiring wafer.

19. The method of manufacturing a LED chip light source of claim 18, wherein the LED functional layer of vertical structure further comprises a metal protective layer; after forming the reflector layer and before forming the first insulating protection layer, the step of forming the LED functional layer of the vertical structure further includes:

the metal protection layer is formed on at least part of the first surface of the second semiconductor layer and the reflector layer.

20. The method of claim 18, wherein the epitaxial layer and the first insulating protective layer are etched to form the scribe line penetrating the epitaxial layer and the first insulating protective layer; or etching the epitaxial layer to form the scribing groove penetrating through the epitaxial layer, and then bending the first insulating protection layer to fracture the first insulating protection layer from the scribing groove; the method comprises the steps of,

and bending the flexible wiring wafer before cutting the flexible wiring wafer along the scribing groove so as to break the second insulating protection layer from the scribing groove.

21. The method of claim 1, wherein the bonding metal material comprises at least two of gold, tin, nickel, silver, and copper.

22. The method of manufacturing a LED chip light source of claim 1, further comprising, prior to bonding the LED wafer to the flexible wiring wafer:

fixing the flexible wiring wafer on a supporting wafer; the method comprises the steps of,

the flexible wiring wafer is separated from the support wafer prior to trimming the flexible wiring wafer.

23. The method of manufacturing an LED chip light source of claim 22, wherein the step of securing the flexible wiring wafer to the support wafer comprises:

forming an adhesive layer on the supporting wafer, and fixing the flexible wiring wafer on the supporting wafer through the adhesive layer; when the material of the bonding layer is a metal material, removing the supporting wafer and the bonding layer by adopting a grinding process so as to separate the flexible wiring wafer from the supporting wafer; and when the material of the bonding layer is an organic adhesive material, decomposing the bonding layer by adopting an organic cleaning solvent so as to separate the flexible wiring wafer from the supporting wafer.

24. The method of claim 22, wherein the thickness of the support wafer is greater than or equal to 250 μm.

25. The method of claim 22, wherein the support wafer is a silicon-containing wafer or a sapphire wafer.

26. The method of claim 22, wherein the first surface of the flexible wiring wafer is fixed to the support wafer and the LED functional layer is bonded to the second surface of the flexible wiring wafer.

27. The method for manufacturing the LED chip light source according to claim 1, wherein the material of the flexible wiring wafer is flexible glass, silica gel or epoxy resin or flexible high molecular polymer containing silicon oxide.

28. The method of manufacturing a LED chip light source of claim 1, wherein the substrate is removed using a laser lift-off process or a grinding process.

29. The method of manufacturing an LED chip light source of claim 1 or 28, further comprising, after removing the substrate:

and coarsening the second surface of the first semiconductor layer of the LED functional layer by adopting alkaline solution.

30. An LED chip light source produced by the production method of an LED chip light source according to any one of claims 1 to 29, comprising:

The flexible substrate is provided with a preset shape and a preset size, and is formed by cutting a flexible wiring wafer; the method comprises the steps of,

the LED functional layer is provided with an electrode surface, is positioned on the flexible substrate and is attached to the flexible substrate, and comprises at least one chip area;

the second surface of the flexible substrate is provided with a metal wiring layer, the electrode surface is attached to the second surface of the flexible substrate, the metal wiring layer comprises at least one wiring area, at least one metal wire is arranged in each wiring area, one chip area is aligned to one wiring area, and the electrode corresponding to each chip area is electrically connected with the metal wire of the corresponding wiring area.

31. The LED chip light source of claim 30, wherein the LED chip light source is a flip-chip LED chip light source and the LED functional layer is a flip-chip LED functional layer.

32. The LED chip light source of claim 31, wherein the flip-chip structured LED functional layer comprises:

the epitaxial layer comprises a first semiconductor layer, a light-emitting layer and a second semiconductor layer which are sequentially arranged from top to bottom;

A recess in the epitaxial layer extending from the first surface of the second semiconductor layer into the first semiconductor layer;

a mirror layer formed on the first surface of the second semiconductor layer and covering a portion of the second semiconductor layer; the method comprises the steps of,

the electrode group is formed on the first surface of the reflector layer and comprises two mutually insulated electrodes, the two electrodes are respectively and electrically connected with the first semiconductor layer and the second semiconductor layer, and the first surface of the electrode is the electrode surface.

33. The LED chip light source of claim 32, wherein the flip-chip structured LED functional layer further comprises:

the current expansion layer is formed on the first surface of the reflector layer and is electrically connected with the second semiconductor layer through the reflector layer;

the connecting metal layer is formed on the first surface of the current expansion layer and fills the groove so as to be electrically connected with the first semiconductor layer, and the connecting metal layer and the current expansion layer are electrically isolated from each other; the method comprises the steps of,

one of the two electrodes is electrically connected with the second semiconductor layer through the current expansion layer, and the other electrode is electrically connected with the first semiconductor layer through the connecting metal layer.

34. The LED chip light source of claim 33, wherein the flip-chip structured LED functional layer further comprises:

the first insulating layer is formed on the first surface of the second semiconductor layer and covers the inner wall of the groove, the first insulating layer is provided with a first opening, one part of the first opening exposes part of the first semiconductor layer at the bottom of the groove, the other part of the first opening exposes part of the second semiconductor layer, and the reflector layer is positioned in the first opening exposing part of the second semiconductor layer.

35. The LED chip light source of claim 34, wherein the flip-chip structured LED functional layer further comprises:

the second insulating layer is formed on the first insulating layer and the first surface of the current expansion layer to electrically isolate the current expansion layer from the connecting metal layer, wherein the second insulating layer is provided with a second opening, one part of the second opening is communicated with one part of the first opening to expose part of the first semiconductor layer, and the other part of the second opening exposes part of the current expansion layer.

36. The LED chip light source of claim 35, wherein the connection metal layer is formed on the first surface of the second insulating layer and fills the first opening and the second opening that are in communication to electrically connect with the first semiconductor layer.

37. The LED chip light source of claim 35, wherein the flip-chip structured LED functional layer further comprises:

and the third insulating layer is formed on the first surfaces of the second insulating layer and the connecting metal layer so as to electrically isolate the two electrodes, wherein the third insulating layer is provided with a third opening, one part of the third opening is communicated with one part of the second opening to expose part of the current expansion layer, and the other part of the third opening exposes part of the connecting metal layer.

38. The LED chip light source of claim 37, wherein two of the electrodes are located on the first surface of the third insulating layer, and one of the electrodes fills the second opening and the third opening in communication to electrically connect with the current spreading layer; the other electrode fills the rest of the third opening so as to be electrically connected with the connecting metal layer.

39. The LED chip light source of claim 31, wherein the flip-chip structured LED functional layer comprises:

the epitaxial layer comprises a first semiconductor layer, a light-emitting layer and a second semiconductor layer which are sequentially arranged from top to bottom;

A recess extending from the first surface of the second semiconductor layer into the first semiconductor layer;

an insulating reflection layer formed on the first surface of the second semiconductor layer and filling the groove; the method comprises the steps of,

the electrode groups are formed on the first surface of the insulating reflecting layer, each electrode group comprises two mutually insulated electrodes, the two electrodes penetrate through the insulating reflecting layer and are respectively and electrically connected with the first semiconductor layer and the second semiconductor layer, and the first surface of each electrode is the electrode surface.

40. The LED chip light source of claim 39, wherein the flip-chip LED functional layer further comprises:

two first-layer metals respectively formed on the first surfaces of the first semiconductor layer and the second semiconductor layer at the bottom of the groove, wherein the two first-layer metals are respectively electrically connected with the first semiconductor layer and the second semiconductor layer; the method comprises the steps of,

both the electrodes pass through the insulating reflecting layer and are respectively and electrically connected with one first layer metal.

41. The LED chip light source of claim 40, wherein the flip-chip LED functional layer further comprises:

A current blocking layer formed on a portion of the first surface of the second semiconductor layer; and

and the current expansion layer is formed on at least part of the first surface of the second semiconductor layer and the first surface of the current blocking layer.

42. The LED chip light source of claim 30, wherein the LED chip light source is a vertically structured LED chip light source and the LED functional layer is a vertically structured LED functional layer.

43. An LED chip light source as recited in claim 42, wherein the vertically structured LED functional layer comprises:

the epitaxial layer comprises a first semiconductor layer, a light-emitting layer and a second semiconductor layer which are sequentially arranged from top to bottom;

a mirror layer formed on a portion of the first surface of the second semiconductor layer;

two insulating protection layers, wherein a first insulating protection layer is formed on the second semiconductor layer and the first surface of the reflector layer, and a second insulating protection layer is formed on the second surface of the first semiconductor layer and the exposed second surface of the flexible wiring wafer;

the electrode groups are formed on the first surface of the first insulating protection layer, and penetrate through the first insulating protection layer to be electrically connected with the second semiconductor layer, the other electrode in the electrode groups is formed on the second surface of the second insulating protection layer, two ends of the electrode groups penetrate through the second insulating protection layer to be electrically connected with the first semiconductor layer and the flexible wiring wafer respectively, and the first surfaces of the electrode groups are the electrode surfaces.

44. The LED chip light source of claim 43, wherein the LED functional layer of the vertical structure further comprises:

and the metal protection layer is formed on at least part of the first surface of the second semiconductor layer and the first surface of the reflector layer.

45. The LED chip light source of claim 30, wherein the flexible substrate is made of flexible glass, silicone or epoxy or a flexible high molecular polymer containing silicon oxide.