CN1187805C - Method for applying heat sink with supporting effect to chip packaging substrate - Google Patents

Abstract

A method for applying a heat sink with supporting effect to a chip package substrate has the advantages of excellent heat dissipation effect, low weight, thin thickness, and capability of eliminating warping and twisting (twist). The firm heat sink with supporting effect is formed by bonding a first heat conductive sheet (i.e. heat sink) and a second heat conductive sheet (i.e. heat sink) with a first adhesive sheet (bonding sheet); the first adhesive sheet is a fiber-reinforced resin. Then, the second adhesive sheet is bonded to a circuit board and the heat sink, wherein the second adhesive sheet is a single-layer adhesive layer or a multi-layer adhesive layer (adhesive of a partial adhesive layers). The adhesive layer is composed of an adhesive, a short-sheet-filled adhesive, a fiber-filled adhesive or a granular-filled adhesive. An opening is formed on the circuit board for the chip to be arranged.

Description

Method for applying heat sink with supporting effect to chip packaging substrate

technical field

The invention relates to a method of electronic packaging, including single-chip and multi-chip packaging, in particular to a method for manufacturing a heat-dissipating chip package with a heat spreader, and the heat spreader also has a supporting effect (stiffener) .

Background technique

With the continuous progress of the semiconductor industry, electronic systems and electronic packages are usually designed to use the smallest space possible practically. Therefore, the space carrying the circuit has become an important resource with technological progress, and should be utilized as much as possible; for this purpose, reducing the circuit is an effective way to make good use of the space, which can increase the operating speed, reduce noise and other manifestations advantage. Such miniaturization is quite satisfactory in the application of many electronic products, such as applications in aircraft, automobiles, mobile phones, laptop computers or portable VCRs. However, the problem of heat dissipation also appears along with the miniaturization, especially the heat generated by the increase of components, which also increases with the increase of the number of transistors on a single semiconductor component.

A form of semiconductor chip packaging that includes one or more chips connected to a substrate, which may be a ceramic substrate with a ceramic material as an insulating layer; or a plastic substrate with a plastic substrate as an insulating layer layer. Traditionally, this packaging substrate is called a chip carrier (chip carrier), which is usually configured and connected to a printed circuit card (printed circuit card) or a printed circuit board (printed circuit board), and the chip can be connected to the substrate in a variety of ways . Generally, the most common method is wire bonding, which is electrically connected by a very fine gold wire from the chip component to the connection point of the substrate; the other is the flip chip connection method, which is connected by a bump The solder bumps are electrically connected as physical contacts of the chip.

Various approaches have been developed for arranging chips on plastic substrates which are less costly than ceramic substrates. The main reason is that plastic substrates have been considered to have more key advantages than ceramic substrates in the operation of chips, including high current carrying capacity, low dielectric constant at short operation delay time (delay time), and low inductance and capacitance. However, the high-temperature stability of the plastic substrate still has problems, and has caused great challenges to the development of the current plastic substrate. One solution is to use a cavity down chip package, which includes a package substrate with an opening capable of receiving the chip, and a heat-dissipating metal block or heat sink attached to the bottom of the chip, and its The open end faces the printed circuit card or printed circuit board.

Figure 1 shows a typical conventional plastic substrate opening down chip package (cavity downplastic chip carrier). The package assembly structure 100 includes a plastic wiring substrate 101 , the plastic wiring substrate 101 is provided with a cavity 102 and a bonding layer 104 bonded with the substrate 101 to dissipate metal blocks or fins 103 . The electrical and/or thermal conductive layer 105 on one side wall can serve as a circuit layer connecting the heat sink 103 and the substrate 101 to improve thermal and electrical conductivity. The chip 106 is located in the recess 102 and attached to the heat sink 103 . The conductive gold wire 107 is used for electrical connection between the chip 106 and the substrate 101 . After the step of laying gold wires, the recess 102 is filled with encapsulant 108 (encapsulant) to cover and protect the conductive gold wires 107 and the chip 106 to avoid environmental corrosion damage. In addition, the external connection pins 109 located on the outermost layer of the substrate serve as the electrical connection between the substrate 101 and the printed circuit board 110 . The external connecting feet can be conductive pins (pins), solder balls or tin pillars, which are respectively applied to plastic pin grid array (PPGA), plastic ball grid array (plastic ball grid array, PBGA) or plastic cylinder array ( plastic column grid array, PCGA) encapsulation.

US Patent No. 5,357,672 discloses a simple cavity down plastic chip carrier method. This method uses a prepreg as an adhesive layer, ie adhesive layer 104 in FIG. 1 or adhesive layer 206 in FIG. 2 . However, according to practical experience, during the hot pressing process of the chip carrier manufactured by this method, the prepreg often warps due to curing shrinkage.

In order to overcome the warping or twisting phenomenon that occurs during the plastic substrate opening-down chip package assembly method, sometimes a stiffener or more copper layers can be added. FIG. 2 shows a typical example, which is another plastic substrate opening-down chip packaging method. A package assembly structure 200, which can also be called a super ball array package (super BGA), includes a circuit board 201 and an inner copper layer ( internal copper layer) 202; the circuit board 201 includes opposite first surfaces 201a and second surfaces 201b, and the first surface 202a of the inner copper layer 202 utilizes an adhesive layer 203 to be connected with the second surface 201b of the circuit board 201 . An opening is formed between the circuit board 201 and the copper layer 202 , so that a cavity 204 penetrates the circuit board 201 and the copper layer 202 . A heat sink 205 is attached to the second surface 202b of the copper layer 202 by an adhesive layer 206 to increase heat dissipation. A chip 207 is placed in the recess 204 and attached to the heat sink 205 by a thermally conductive adhesive layer 208 . The conductive gold wire 209 serves as the connection between the chip 207 and the circuit board 201 . After the gold wire forming step, the recess 204 is filled with an encapsulant 210 (encapsulant) to cover and protect the conductive gold wire 209 and the chip 207 to avoid environmental corrosion damage. The solder balls 211 are disposed at appropriate positions on the first surface 201 a of the circuit board 201 , and are electrically connected to the printed circuit board 212 . Another common structure is that an additional heat sink can also be directly attached to the second surface 205b of the heat sink 205 to achieve a better heat dissipation effect.

U.S. Patent No. 6,034,427 also discloses a method of opening downward BGA with a support. First, a strong support (stiffener) is pasted on a circuit board by means of a prepreg (prepreg), and then an adhesive Layers attach the fins to this solid support. The heat sink used in this patent is a copper base material (copper base material), that is, common soft materials such as copper or copper alloys, and the curing shrinkage of the adhesive layer will make the hot-pressed heat sink and the supporting body The warping phenomenon is caused in the circuit board process.

U.S. Patent No. 6,060,778 also discloses a simple opening-down BGA method, which has the advantages of excellent heat dissipation effect, low weight, thin thickness and low manufacturing cost. This patent teaches to use the first heat conduction thin plate to be adhered to the circuit board first, and then to connect with the circuit board containing the first heat conduction thin plate with a second heat conduction thin plate (ie heat sink). This method is shown schematically in Figure 7 of the patent specification. However, this patent also encounters the same problem as the aforementioned U.S. Patent No. 6,034,427: that is, it is difficult to eliminate the warpage caused by the method.

Contents of the invention

Therefore, the present invention provides a chip packaging method with the plastic substrate opening downward, which has the advantages of excellent heat dissipation effect, low weight, thin thickness, elimination of warping and twisting, and low manufacturing cost.

According to the method proposed by the present invention, firstly, two heat conduction thin plates are bonded together to form a heat sink, and then the heat sink is bonded to a circuit board (or packaging substrate) with an opening downward, which is obviously different from the U.S. Patent The methods proposed in US6,034,427 and US6,060,778, according to the statement of these two patents, all use a heat conduction thin plate to bond with a plastic substrate first, and then the circuit board with a heat conduction thin plate and another A thermally conductive thin plate is bonded. Yet another obvious difference is that the present invention uses prepreg as the adhesive layer between the two thermally conductive sheets, and uses non-prepreg adhesive material as the adhesive layer between the substrate and the thermally conductive sheet for lamination. , but on the contrary, the method proposed by US Patent No. 6,034,427 uses non-prepreg adhesive material as the adhesive layer between the two thermally conductive sheets, and uses prepreg as the adhesive layer between the substrate and the thermally conductive sheet. Layers are bonded together. According to the method proposed by the present invention, two or more thermally conductive thin plates are laminated with prepreg as an adhesive layer, and the formed heat sink has high mechanical strength characteristics, so when it is laminated with a circuit board, As a support, it can be used to prevent warping or twisting.

The purpose of the present invention is to provide a method for applying a solid heat sink with supporting effect to a chip packaging substrate, which has the advantages of excellent heat dissipation effect, low weight, thin thickness, and no warping and twisting.

According to one aspect of the present invention, the provided method for applying a heat sink with a supporting effect to a chip package substrate includes the following steps: a) providing a plastic circuit substrate having opposite first and second surfaces, the circuit substrate comprising There is at least one opening for loading chips; b) providing a first thermally conductive sheet with opposite first surfaces and second surfaces; c) providing a first thermally conductive sheet with opposite first surfaces and second surfaces A second heat conduction thin plate, the second heat conduction thin plate includes at least one opening for loading chips; d) bonding the first surface of the first heat conduction thin plate to the second heat conduction thin plate with a first adhesive sheet The second surface of the bonding sheet is connected, the first adhesive sheet is composed of a prepreg (prepreg) of fiber-reinforced resin (fiber-reinforced resin); e) the first adhesive sheet is made of non-prepreg Two adhesive sheets connect the first surface of the second thermal conductive sheet with the second surface of the circuit substrate.

According to another aspect of the present invention, the provided method for applying a heat sink with a supporting effect to a chip packaging substrate includes the following steps: a) providing a plastic circuit substrate having opposite first and second surfaces, the circuit substrate and may include at least one opening for loading chips; b) providing a thermally conductive sheet with opposite first and second surfaces; c) providing a thermally conductive sheet with opposite first and second surfaces A heat conduction thin plate laminate on the surface, and the heat conduction thin plate laminate may include at least one opening for loading chips; d) bonding the first surface of the heat conduction thin plate to the first surface of the heat conduction thin plate with a first adhesive sheet The second surface of the thermally conductive sheet laminate is bonded, and the first bonded sheet is composed of a fiber-reinforced resin prepreg; e) non-prepreg ) to bond the first surface of the thermally conductive sheet laminate to the second surface of the circuit substrate.

In addition, the present invention provides a first adhesive sheet (bonding sheet) that can bond a first thermally conductive sheet (thermally conductive sheet) and a second thermally conductive sheet to form a strong heat sink, and the first adhesive sheet It can be fiber-reinforced resin, and the second heat conduction thin plate has an opening for accommodating an electronic chip.

In addition, the present invention provides a second bonding sheet capable of bonding a plastic circuit board with an opening for accommodating a chip to a solid heat sink structure. The adhesive sheet is composed of a single-layer adhesive layer or a multi-layer adhesive layer laminated, and the adhesive layer is composed of adhesive material, flake-filled adhesive material, fiber-filled adhesive It is composed of adhesive material or particle-filled adhesive material, and it is not prepreg material.

The purpose, features and effects of the present invention will be described in detail below in conjunction with the accompanying drawings. Of course, the present invention can be implemented in many different ways, and is not limited to the content described in this specification. What is disclosed in the description below is quite complete and can fully express the spirit to be disclosed in the present invention.

Description of drawings

FIG. 1 is a schematic diagram of an open-down chip packaging method in the conventional technology.

FIG. 2 is a schematic diagram of another conventional technology of opening-down chip packaging with supports.

FIG. 3 is a schematic view of various layers forming an opening-down circuit board attached with a heat sink structure in the first embodiment of the present invention.

Fig. 4 is a schematic diagram of the heat sink structure in another embodiment of the present invention.

FIG. 5 is a schematic diagram of forming a sharp-edge connector structure as sharp as a knife edge in another embodiment of the present invention.

FIG. 6 is a schematic diagram of an opening-down circuit board structure formed with heat sinks having a plurality of thermally conductive thin plates in another embodiment of the present invention.

7 is a schematic diagram of forming an open-down circuit board with heat sink for multi-chip packaging according to another embodiment of the present invention.

Explanation of reference numerals: 1, 30, 32, 101, 201 - substrate; 2, 11, 27, 33, 34 - opening; 3 - layer; 4 - first surface of substrate; 5 - second surface of substrate; 6 - second 1. heat conduction thin plate; 7-the first surface of the first heat conduction thin plate; 8-the second surface of the first heat conduction thin plate; 9-adhesion enhancer; 10-the second heat conduction thin plate; 12-the first heat conduction thin plate Surface; 13-the second surface of the second heat conduction thin plate; 14,15,29-adhesion enhancer; 16,19,31,36-adhesive sheet; 17,28,35-heat sink structure; 17a-protective layer; 18, 18a, 105-conductive or/and thermally conductive layer; 20-joint portion with sharp ends; 22-first thermally conductive sheet; 23-second thermally conductive sheet; 25-first adhesive sheet; 26-thermally conductive Thin plate laminate; 100, 200-package assembly structure; 101, 201-substrate; 102, 204-depression; 103, 205-heat sink; 104, 206-adhesive layer; 106, 207-chip; -gold wire; 108,210-seal glue; 109,211-connection pin; 110,212-circuit board; 202-copper layer; 202a-copper layer first surface; 202b-copper layer second surface; 203,206, 208—adhesive layer; 205a—the first surface of the heat sink; 205b—the second surface of the heat sink.

Detailed ways

The invention relates to a method for applying a solid heat sink with a supporting effect to a chip packaging substrate, in particular to a chip packaging method for a heat-dissipating integrated circuit with the opening facing down that eliminates warping and twisting in the method. At the same time, this package can also maintain a good heat dissipation effect. However, the illustrations of the present invention are only for simple illustration, and are not drawn according to the actual scale, that is, they do not reflect the actual size and characteristics of each layer in the chip carrier structure.

Please refer to FIG. 3 , which is the first embodiment of the present invention. Firstly, a chip plastic carrier substrate 1 is provided, and the substrate 1 includes an opening 2 and several layers 3 . The substrate 1 may include conventional wiring circuit layers, through-holes, conductive through-holes, or vias separated by an organic insulating layer; electrodes on the surface of the layer 3 (or bonding finger, bonding finger) and protective layer; electrodes (or welding pads, landing pads), barrier (dam) and protective coating on the first surface 4 of the layer; welding pads on the second surface 5 and protective cladding etc. The first thermally conductive sheet (thermally conductivesheet) 6 (or heat sink), the first thermally conductive sheet 6 can be a copper or copper alloy sheet, graphite fiber filled copper or copper alloy, graphite fiber filled aluminum or aluminum alloy, Copper or copper alloy filled with silicon carbide particles, aluminum or aluminum alloy filled with silicon carbide particles, etc., can be chemically or physically roughened on both the first surface 7 and the second surface 8 . The first surface 7 is formed with an adhesion promoter 9 (adhesion promoter), preferably an oxide layer or a coupling agent (coupling agent), to increase its adhesion. The coupling agent may include silane coupling agent (silane), titanium coupling agent, cobalt coupling agent or aluminum coupling agent and the like. The second heat conduction thin plate 10 (or claim inner layer heat conduction thin plate), it is provided with an opening 11 to penetrate wherein, similarly, this second heat conduction thin plate 10 can be copper or copper alloy thin plate, the copper or copper that graphite fiber fills alloy, graphite fiber-filled aluminum or aluminum alloy, silicon carbide particle-filled copper or copper alloy, silicon carbide particle-filled aluminum or aluminum alloy, etc., and can be chemically or physically roughening step, and the first surface 12 and the second surface 13 are formed with adhesion enhancers 14 and 15 . However, the adhesion enhancer is not limited to the oxide layer or coupling agent described in the present invention. The first surface 7 of the first heat conducting thin plate 6 is attached to the second surface 13 of the second heat conducting thin plate 10 via an adhesive sheet 16 . The adhesive sheet 16 is preferably fiber-reinforced resin, such as prepreg. Through the heat-pressing step, a stiff heat spreader element 17 comprising the first heat-conducting thin plate 6 and the second heat-conducting thin plate 10 is then completed. After the bonding sheet 16 (prepreg) is cured by hot pressing, the heat sink structure 17 becomes a solid sandwich structure. The thermally conductive or electrically conductive layer 18 can be used as a thermal connection between the first thermally conductive thin plate 6 and the second thermally conductive thin plate 10 to further enhance the heat dissipation effect. In addition, the first thermally conductive thin plate 6 and the second thermally conductive thin plate 10 can be configured to have equal thicknesses, and this symmetrical sandwich structure can obtain the best effect of preventing warping and twisting.

Another embodiment is shown in FIG. 4 , wherein a thermal or electrical conductive layer 18 a can be a thin copper or copper alloy layer, etc., and can be formed on the lower surface of the heat sink structure 17 . Of course, before forming the thermal or electrical conductive layer 18 or 18a, steps such as acid cleaning or plasma cleaning (plasmacleaning) may be performed on the lower surface of the heat sink structure 17 first. A protective layer (not shown) can be formed on the second surface 8 of the first thermally conductive thin plate 6, such as nickel, gold or thermally conductive particle-filled epoxy resin (epoxy resin), diamond film or diamond-like carbon film, etc. , and before forming the protective layer, the second surface 8 of the first thermally conductive thin plate 6 can be roughened physically or chemically. The second adhesive sheet 19 is disposed between the first surface 12 of the second heat conducting sheet 10 and the second surface 5 of the substrate 1 . After the pressing step, the heat sink structure 17 is bonded to the second surface 5 of the substrate 1 after the second adhesive sheet 19 is hardened by heating or radiation. After general conventional methods such as sidewall plating, chip placement, gold wiring, filling and sealing, and outer layer terminal pin placement, the open-down chip package assembly structure 200 shown in FIG. 2 can be formed in this way.

According to the method proposed by the present invention, as shown in FIG. 4, the heat or electrical conduction layer 18a has connected the first heat conduction thin plate 6 and the second heat conduction thin plate 10 by heat transfer, which can further improve the heat dissipation effect; but US Patent No. 6, The method proposed in 034,427 and US 6,060,778 cannot obtain the advantage of improving the heat dissipation effect, because it first joins a heat conduction thin plate and a circuit board, rather than the method proposed by the present invention, two or more heat conduction thin plates Bonding is performed first, followed by bonding to a circuit board.

The chip carrier plastic substrate 1 can be a single-layer or multi-layer substrate, and the substrate is composed of a dielectric material (for forming an insulating layer) and a conductive material alternately overlapping, and the dielectric material can be organic Materials, fiber-reinforced organic materials or particle-reinforced organic materials, such as epoxy resin, polyimide, bismaleimide/ Triazine (bismaleimide triazine), cyanate ester (cyanate ester), polybenzocyclobutene (polybenzocyclobutene) or its glass fiber composition. The plastic chip carrier substrate 1 is preferably completed before being bonded with the heat sink structure 17, so that via holes can be formed through the substrate 1 to form an opening-down chip package assembly structure. According to the present invention, when the substrate 1 and the heat sink structure 17 are bonded, since the substrate has been cured and shaped in advance, the cure shrinkage during the formation of the substrate 1 will not cause any warping or twisting.

Please refer to FIG. 1 again, the heat sink 103 is usually made of copper or copper alloy. It is well known that when the actual operating temperature is between 300-400°C, the copper sheet will soften. Therefore, if the copper thickness of the heat sink 103 is too thin, less than 0.5mm, when the heat sink 103 in the plastic substrate chip package assembly structure 100 is manufactured, it will be difficult to control because the heat sink 103 is easily deformed, resulting in a method Great trouble. Therefore, the thickness of the copper heat sink 103 should be at least 0.5 mm. However, if a thin heat sink 103 (thinner than 0.5 mm in thickness) is required, it is always better to form the heat sink 103 with a copper alloy with higher mechanical strength, preferably with a thickness of 0.1 mm or more. The proportion of added alloy components of the copper alloy should account for less than 5% of the total copper alloy weight, such as C194 or C305 copper alloy; preferably, the proportion of added alloy components should account for less than 0.5% of the total copper alloy weight, such as C151 copper alloy , because the addition of a higher alloy composition will make the copper alloy have lower thermal conductivity (thermally conductivity). It should be noted here that the "copper" mentioned in the present invention refers to a copper alloy whose alloy component content is unavoidably below 0.1% by weight.

However, when the sandwich-type heat sink structure 17 of the present invention is applied, the restriction that the thickness of the copper heat sink needs to be above 0.5 mm can be removed. For example, the first heat conduction thin plate 6 and the second heat conduction thin plate 10 with a thickness of 0.254mm can be combined with a prepreg material to form a heat sink 17, which has sufficient hardness and strength for forming the package assembly structure 200. Thickness can overcome the warping phenomenon in the method of forming the chip carrier; at this time, the adhesive layer 16 between the first thermally conductive sheet 6 and the second thermally conductive sheet 10 can also be made of two or more prepregs The composition can further increase the mechanical strength of the heat sink structure. Preferably, the first thermally conductive thin plate 6 and the second thermally conductive thin plate 10 have the same thickness, which will have the best effect on eliminating the warping phenomenon in the method of forming the chip carrier.

In order to make the heat sink structure 17 completely prevent environmental erosion, a protective layer 17a can be covered on the side walls around the heat sink 17, such as nickel, gold, epoxy resin filled with thermally conductive particles, diamond film, diamond-like carbon film, etc. . When the protective layer 17a covers the surrounding sidewalls of the heat sink 17, the heat dissipation effect can also be improved at the same time due to the increased surface area.

In the embodiment of the present invention, the adhesive sheet 19 is composed of one adhesive layer or laminated multiple adhesive layers. The adhesive layer is, for example, an adhesive material, a flake-filled adhesive, a fiber-filled adhesive or a particle-filled adhesive. Since the braided fibers are not filled in the adhesive material, the adhesive layer of the present invention is not a prepreg. The adhesive layer can be (1) resin, such as epoxy resin, polyimide resin (polyimide resin), polyurethane (polyurethane) or acrylic resin (acrylic), etc.; (2) copolymer (copolymer), such as epoxy- Acrylic resin (epoxy-acrylic resin), epoxy-butadiene resin (epoxy-butadieneresin) or epoxy-urethane resin (epoxy-urethane), etc.; (3) polymer compound, such as epoxy resin / Halogenated polyhydroxystyrene resin blend (epoxy resin/halogenated polyhydroxystyrene blend) or epoxy resin/phenol resin blend (epoxy resin/phenol resin blend), etc. The organic material can be modified by halogen, silicone or phosphite. Described short fiber (short fiber) is made with metal, organic or inorganic material, as tungsten short fiber, aromatic polyamide (aramid) short fiber or glass short fiber etc., can fill described organic material to increase Mechanical strength and reduce the coefficient of thermal expansion of the adhesive layer. For the same purpose, small flakes or particles can be added to organic materials, such as silver flakes or graphite flakes (graphite), and granular materials such as silica particles, barium sulfate particles, clay ), calcium carbonate, milamine particles, polystyrene (polystyrene), copper particles or silver particles, etc. The adhesive layer may also contain other additives, such as chemical catalysts, antioxidants, rheological agents, coupling agents, or color agents.

The selection of the adhesive material is very important to reduce warping or twisting during the manufacture of the chip carrier with the opening facing downward. In today's industry, adhesive materials are mainly based on thermosetting resins. Typical thermosetting resins are cured at higher temperatures and cooled at room temperature. Therefore, preferably, the material of the adhesive layer is soft enough (that is, has a low mechanical modulus), and the material can expand and deform to compensate for curing shrinkage during the curing step. Normally, reducing the coefficient of thermal expansion (CTE) of the adhesive layer and partially curing the thermosetting resin before processing will help to obtain good adhesion with low warpage. However, prepreg materials with substantially high mechanical coefficients are difficult to provide good adhesion to chip carriers with openings facing downward. To achieve good adhesion, too high a filler loading to provide higher mechanical properties, or too low a filler loading to provide a higher coefficient of thermal expansion must be avoided. In addition, the coefficient of thermal expansion of the adhesive layer is preferably below 150 ppm/°C, more preferably below 100 ppm/°C, and most preferably 50 ppm/°C.

In a preferred embodiment of the present invention, the first adhesive sheet 16 and the second adhesive sheet 19 are not limited to any shape or structure.

In another preferred embodiment of the present invention, the heat sink structure may be provided with a sharp-edge connector that is as sharp as a knife edge. As shown in FIG. 5 , several sharp-edged connecting portions 20 are formed on the first surface 12 of the second thermally conductive thin plate 10, and the first surface 12 is also covered with an adhesion enhancer 14, such as an oxide layer or coupling agent, etc. . The sandwich-type heat sink structure 17 is bonded to the substrate 1 by means of thermal pressing through the adhesive sheet 19 . At the same time, each of several knife-edge-sharp connecting portions 20 also penetrates the adhesive sheet 19 and connects with predetermined contact pads (contact pads) (not shown) on the second surface 5 of the substrate 1 . Of course, the adhesive sheet 19 can also be drilled at the connecting position by laser drilling or mechanical drilling before bonding, which will be more helpful for the connecting portion 20 to penetrate the adhesive sheet 19 and connect with the predetermined contact pad. Each of the plurality of knife-edge-sharp connecting portions 20 is electrically conductive or thermally conductive, and can be in any shape and structure. This type of connection enables the heat sink structure 17 to participate in the role of "grounding" and provide a heat conduction path to conduct heat generated inside the chip. In this way, the thermal and electrical conductivity of the opening of the plastic substrate to the chip carrier can be improved.

In another preferred embodiment of the present invention, the heat sink structure can use two or more heat conducting thin plates. As shown in Figure 6, the second heat conduction thin plate 23 utilizes the first adhesive sheet 25 to bond with another second heat conduction thin plate 23 to form a heat conduction thin plate composite 26, and the heat conduction thin plate 26 has a capacity The opening 27 of the chip is placed, and the heat conduction sheet laminate 26 is combined with the first heat conduction sheet 22 by another first adhesive sheet 25 to form a heat sink structure 28 . Adhesion enhancer 29 , such as oxide layer or coupling agent, can be formed on the outer surface of each thermal conductive thin plate 22 , 23 to increase its adhesiveness. The heat sink structure 28 can be combined with the plastic circuit substrate 30 through the second adhesive sheet 31 to form a plastic chip carrier with an opening downward. Wherein the first adhesive sheet 25 is a prepreg material, and the second adhesive sheet 31 is composed of a single-layer adhesive layer or a laminated multi-layer adhesive layer. The adhesive layer can be an adhesive material or an adhesive material filled with small flakes. , fiber-filled adhesive or granular-filled adhesive.

In another preferred embodiment of the present invention, the chip carrier is not limited to single-chip or multi-chip packages. A typical multi-chip packaging method is shown in FIG. 7 , a circuit substrate 32 includes two openings 33 , 34 , and each opening can accommodate a chip. The heat sink structure 35 is bonded to the circuit substrate 32 by means of an adhesive sheet 36 in a thermocompression manner to form a multi-chip carrier.

In a preferred embodiment of the present invention, when the chip carrier is mass-produced in the industry, the sandwich-type heat sink panel can be bonded to the circuit substrate panel by means of an adhesive sheet. The panels can be of any shape or structure, such as strips and the like.

In a preferred embodiment of the present invention, the chip carrier is not limited to semiconductor chip packaging, but can also be applied to electronic components, optical components or optoelectronic components of other chip types, such as resistors ( resistor), oscillators, laser diodes, optical sensors and thermal sensors, etc.

To sum up, the present invention discloses a method of applying a heat sink with a supporting effect to a chip packaging substrate, which can eliminate warping or twisting in the method, and provide good adhesion and high heat resistance between circuit layers and a method with good reliability.

Of course, the above descriptions are only preferred embodiments of the structure and method of the circuit substrate of the present invention, and are not intended to limit the present invention. Any modifications made by those skilled in the art without violating the spirit of the present invention shall belong to the scope of the present invention, so the scope of protection of the present invention shall be based on the claims.

Claims (14)

1, a kind of fin with support effect is applied to the chip package base plate method, may further comprise the steps:

(a) provide the plastic circuit substrate with opposite first and second surface, this circuit substrate includes at least more than one can be for the opening that loads chip;

(b) provide the first thermal conductance thin plate with opposite first and second surface;

(c) provide the second thermal conductance thin plate with opposite first and second surface, this second thermal conductance thin plate includes at least more than one can be for the opening that loads chip;

(d) with first adhesive sheet first surface of the described first thermal conductance thin plate and the second surface of the second thermal conductance thin plate are connected, this first adhesive sheet is made up of the preimpregnation material of fiber-reinforced resin;

(e) be selected from the second made adhesive sheet of not strengthening of the non-preimpregnation adhesive layer of the mixing thing of fluoropolymer resin, copolymer resin, polymer with one deck at least, the first surface of the described second thermal conductance thin plate and the second surface of circuit substrate are connected with braided fiber.

2, the fin with support effect as claimed in claim 1 is applied to the chip package base plate method, and the wherein said first thermal conductance thin plate or the second thermal conductance thin plate are metal material.

3, the fin with support effect as claimed in claim 1 is applied to the chip package base plate method, and the wherein said first thermal conductance thin plate is the metal material of fibre strengthening or particle strengthening.

4, the fin with support effect as claimed in claim 1 is applied to the chip package base plate method, and the wherein said second thermal conductance thin plate is the metal material of fibre strengthening or particle strengthening.

5, the fin with support effect as claimed in claim 1 is applied to the chip package base plate method, and wherein said first adhesive sheet is superimposed by single or multiple lift preimpregnation material.

6, the fin with support effect as claimed in claim 1 is applied to the chip package base plate method, and wherein this second adhesive sheet is made up of the single or multiple lift adhesion layer.

7, the fin with support effect as claimed in claim 6 is applied to the chip package base plate method, and wherein this adhesion layer is the material of sticking together that short fiber is filled, thin slice is filled or shot-like particle is filled.

8, a kind of fin with support effect is applied to the chip package base plate method, may further comprise the steps:

(a) provide the plastic circuit substrate with opposite first and second surface, this circuit substrate also can include the opening that at least more than one can supply to load chip;

(b) provide a thermal conductance thin plate with opposite first and second surface;

(c) provide the thermal conductance sheet pack compound with opposite first and second surface, this thermal conductance sheet pack compound also can include the opening that at least more than one can supply to load chip;

(d) with first adhesive sheet first surface of described thermal conductance thin plate and the second surface of described thermal conductance sheet pack compound are connected, this first adhesive sheet is made up of the preimpregnation material of fiber-reinforced resin;

(e) being selected from the second made adhesive sheet of not strengthening with braided fiber of the non-preimpregnation adhesive layer of the mixing thing of fluoropolymer resin, copolymer resin, polymer with one deck at least is connected the first surface of described thermal conductance sheet pack compound and the second surface of circuit substrate.

9, the fin with support effect as claimed in claim 8 is applied to the chip package base plate method, and the wherein said thermal conductance thin plate system that coincides forms as the pressing of adhesion layer institute with first adhesive sheet at least two above thermal conduction plates.

10, the fin with support effect as claimed in claim 8 is applied to the chip package base plate method, and wherein said thermal conductance thin plate is a metal material.

11, the fin with support effect as claimed in claim 8 is applied to the chip package base plate method, and wherein said thermal conductance thin plate is the metal material of fibre strengthening or particle strengthening.

12, the fin with support effect as claimed in claim 8 is applied to the chip package base plate method, and wherein said first adhesive sheet is superimposed by single or multiple lift preimpregnation material.

13, the fin with support effect as claimed in claim 8 is applied to the chip package base plate method, and wherein this second adhesive sheet is made up of the single or multiple lift adhesion layer.

14, the fin with support effect as claimed in claim 13 is applied to the chip package base plate method, and wherein this adhesion layer is the material of sticking together that short fiber is filled, thin slice is filled or shot-like particle is filled.

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