TWI394219B - Electrical connection method of semiconductor packages and a peelable adhesive flexible board used for the same - Google Patents

Description

Electrical connection method for semiconductor package and tearable viscous flexible board used therefor

The present invention relates to a semiconductor device, and more particularly to a method of electrically connecting a semiconductor package and a tearable viscous flexible board for use therewith.

Currently, in a semiconductor package structure, a plurality of wafers of the same memory capacity are allowed to be stacked and packaged in the same package to achieve a function of twice or more than a capacity, for example, a memory capacity of two or more memories is 512 M or more. The wafer stack is combined and packaged into a package structure having a memory capacity of 1024 M or more, a so-called "multi-wafer stacked package". Conventionally, semiconductor wafers used can be classified into a central pad type wafer and a peripheral pad type wafer. In particular, when the central pad type wafer is stacked with the active surface (ie, the integrated circuit forming surface) facing upward, it is necessary to wire a long bonding wire to electrically connect the wafer to the substrate. The use of active face-up multi-wafer stack packaging products can be used as a film overfill (FOW) as a wafer spacer fill and protective bond wire, but because the bond wire connecting the center pad is long, there will be Excessive line arcs and long and non-fixed wire bodies between the wafers make it easy for the wire to touch the upper and lower wafers causing a short circuit and the risk of twisting.

As shown in FIG. 1 , a conventional multi-wafer stack structure using wire bonding mainly includes a substrate 110 , a first wafer 120 , a first bonding wire 130 , a second wafer 150 , and a second bonding wire 170 . The first wafer 120 is disposed on the substrate 110 in an active face-up manner, and the active surface 121 of the first wafer 120 is formed with a plurality of first pads 122. The first bonding wires 130 and the second bonding wires 170 are gold wires formed by wire bonding. The first bonding wires 130 are electrically connected to the first pads 122 of the first wafer 120 to the fingers 111 of the substrate 110 . The second wafer 150 is disposed on the active surface 121 of the first wafer 120 by a Film Over Wire (FOW), and the wire bonding layer 160 covers the first bonding wires. A line segment above the active surface 121. The active surface 151 of the second wafer 150 has a plurality of second pads 152, and the second bonding wires 170 electrically connect the second pads 152 to the fingers 111 of the substrate 110. In the process of affixing the second wafer 150, the Film Over Wire (FOW) may be formed on the back surface of the second wafer 150, and when the second wafer 150 is attached to the first The wafer 120 is pressed and heated to coat the first bonding wires 130 with the first bonding wire 130. However, since the overcoat layer 160 must be capable of reducing the line arc of the first bonding wires 130, the first bonding wires 130 are prevented from contacting the back surface of the first wafer 120. The first bonding wires 130 cause a certain pressing force. Conditions such as temperature and pressure are inadvertently operated, often causing the first bonding wires 130 to cause twisting or excessive deformation, and even touching the active surface 121 of the first wafer 120 or the bonding wires touching each other to cause a short circuit, resulting in a product Poor reliability and reduced process speed. In addition, in order to enable the wire bonding layer 160 to cover the first bonding wires 130, and the first bonding wires 130 have a certain arcing height, the thickness of the wire bonding layer 160 can only be made. Maintaining a predetermined value that cannot be reduced, this increases the overall package height.

Therefore, at present, wire bonding is used as an electrical connection method for a semiconductor package, and a gold wire is usually used as a wire bonding material, which has a relatively expensive material cost. In particular, the larger the number of wafer stacks of the central pad type wafer, the more complicated or long wire bonding processes must be faced, the more prone to twisting, and the risk of wire collapse or contact with the edge of the wafer. Once the traditional wire bonding method is applied to the multi-wafer stacked products, since the bonding wires are used to achieve electrical connection, as the number of wafer stacks increases, it is easier to derive various kinds of bonding wires in the subsequent packaging process. The problem is not applicable to packaged products with small pitch (fine-pitch, which means that the pitch of the wire is no more than 50 microns).

The main purpose of the present invention is to provide a method for electrically connecting a semiconductor package and a tearable flexible flexible board for use thereof, which can completely eliminate the problem of the twisting line of the conventional wire bonding, and further avoid the risk of causing the wire to collapse and contact the wafer. It is especially suitable for small line spacing and replaces complex or long wire bonding processes, improving the package's ability and reliability.

A second object of the present invention is to provide a method for electrically connecting a semiconductor package and a tearable flexible flexible board used thereby, which can improve the overall packaging process efficiency and reduce the manufacturing cost.

A further object of the present invention is to provide a method for electrically connecting a semiconductor package and a tearable flexible flexible board therefor, which can replace the bonding wire to eliminate the line arc, and can reduce the wafer stacking gap when applied to the multi-wafer stacking. And bubbles are not easily generated in the wafer stack gap.

The object of the present invention and solving the technical problems thereof are achieved by the following technical solutions. The invention discloses an electrical connection method for a semiconductor package, which mainly comprises the following steps: providing a substrate having a plurality of fingers. A first wafer is disposed on the substrate, and a plurality of first pads are disposed on the active surface of the first wafer. A plurality of first bumps are disposed on the first pads. A tear-off viscous flexible sheet is disposed on the first wafer, wherein a viscous surface of the detachable viscous flexible board is adhered to a plurality of flexible inner leads. A first pressure bonding step is performed to bond the flexible inner leads to the first bumps. A second pressure welding step is performed to bond the flexible inner leads to the fingers. The tearable viscous flexible sheet is torn away to leave the flexible inner leads between the first wafer and the substrate. The present invention further discloses a tear-off viscous flexible board applied to the above electrical connection method.

The object of the present invention and solving the technical problems thereof can be further achieved by the following technical measures.

In the foregoing electrical connection method of the semiconductor package, after the first bumps are disposed and before the tearable viscous flexible board is disposed, the method may further include: covering an insulating coating layer on the first The active surface of the wafer exposes the first bumps for adhesion of the tearable viscous flexible board, and the insulating coating layer is a soft rubber layer.

In the foregoing electrical connection method of the semiconductor package, the main system of the tearable flexible flexible board may be a UV adhesive film, and the UV adhesive is further reduced by ultraviolet light irradiation after the two pressure welding steps. Adhesion of the adhesive film to the flexible inner leads.

In the above electrical connection method of the semiconductor package, the flexible inner leads may be copper wires, and the outer edges of the flexible inner leads are covered with a gold layer.

In the above electrical connection method of the semiconductor package, the first pads may be disposed at the center of the active surface of the first wafer, and the flexible inner leads are staggered in a comb shape.

In the foregoing method of electrically connecting the semiconductor package, the method further includes the steps of: disposing a second wafer on the first wafer, and forming a first adhesive layer on the first wafer and the second wafer For bonding the first wafer and the second wafer and partially covering the flexible inner leads.

In the foregoing electrical connection method of the semiconductor package, the first wafer and the second wafer system may have the same size and function, and the active surface of the second wafer is provided with a plurality of second pads.

In the foregoing electrical connection method of the semiconductor package, after the step of disposing the second wafer, the method further includes the step of: providing a plurality of second bumps on the second pads. A second tear-off viscous flexible sheet is disposed on the second wafer, wherein a viscous surface of the second detachable viscous flexible board is adhered to the plurality of second flexible inner leads. A third pressure bonding step is performed to bond the second flexible inner leads to the second bumps. A fourth pressure bonding step is performed to bond the second flexible inner leads to the fingers. The second flexible adhesive flexible sheet is peeled off to leave the second flexible inner leads between the second wafer and the substrate.

In the foregoing electrical connection method of the semiconductor package, after the second bumps are disposed and before the second flexible adhesive flexible board is disposed, the method further includes: covering a second insulating coating layer And forming the second bumps on the active surface of the second wafer for adhesion of the second tearable flexible flexible board.

In the above electrical connection method of the semiconductor package, the adhesive surface may be adhered to a pin bus bar having at least one extension pin and the flexible inner pins. Side by side.

In the above electrical connection method of the semiconductor package, the flexible inner leads may include a plurality of first side inner pins and a plurality of second side inner pins fanned in different directions, the pin The busbar passes through a gap between the first side inner pin and the second side inner pins.

In the above electrical connection method of the semiconductor package, the first pads may be composed of a plurality of first row pads and a plurality of second row pads, and the tearable flexible board is disposed on the In the first wafer, the inner ends of the first inner pins are aligned with the first row of pads, and the inner ends of the second side inner leads are aligned with the second rows of pads pad.

It can be seen from the above technical solutions that the electrical connection method of the semiconductor package of the present invention and the tearable flexible flexible board used thereof have the following advantages and effects:

1. As a technical means by covering the insulating coating layer and attaching a tearable flexible flexible board having a flexible inner lead, since the tearable adhesive flexible board adheres to the flexible inner lead And electrically connecting the wafer and the substrate through the flexible inner lead, so that the problem of the conventional wire bonding can be completely eliminated, and there is no need to worry about the risk of causing the wire to collapse and contact the chip, especially for small line spacing and replacing the complex. Or long wire bonding process, which improves the package's ability and reliability.

Second, by attaching a tearable viscous flexible board with a flexible inner lead as one of the technical means, since the tearable viscous flexible board is adhered with a flexible inner lead, flexibility is achieved. The inner pin is aligned with the gold finger and the gold finger, and the electrical connection relationship is achieved, so that the previous wire bonding process can be replaced, and the overall packaging process efficiency is improved.

3. A flexible floppy flexible board with a flexible inner lead can be attached as one of the technical means. Since the flexible inner lead is made of copper wire, it is only for the flexible inner lead. The outer layer is covered with a gold layer, which can reduce the material cost and is lower than the gold wire used in the past.

Fourth, by attaching a tearable flexible flexible board with a flexible inner lead as one of the technical means, since the flexible inner lead can be substituted for the bonding wire to eliminate the line arc, it is applied to the multi-wafer stacking. The wafer stack gap can be reduced and bubbles are not easily generated in the wafer stack gap. Therefore, more wafers can be stacked with the same package thickness as conventional.

The embodiments of the present invention will be described in detail below with reference to the accompanying drawings in which FIG. The components and combinations related to this case, the components shown in the figure are not drawn in proportion to the actual number, shape and size of the actual implementation. Some size ratios are proportional to other related sizes or have been exaggerated or simplified to provide clearer description of. The actual number, shape and size ratio of the implementation is an optional design, and the detailed component layout may be more complicated.

According to a first embodiment of the present invention, a method of electrically connecting a semiconductor package is illustrated in a block diagram of FIG. 2 and a cross-sectional view of an element of FIGS. 3A to 3I. According to FIG. 2, the electrical connection method of the semiconductor package may include the following steps: step 1 of “providing a substrate”, step 2 of “providing a wafer on the substrate”, and “setting a first bump on the pad of the wafer” Step 3, Step 4 of "covering the insulating coating layer on the active surface of the wafer", Step 5 of "Setting the tearable viscous soft board on the wafer," Step 5, "Step 1 of performing the first pressure welding" Step 7 of "Second Pressure Welding" and Step 8 of "Tear Off Removable Viscous Soft Board", please refer to Figures 3A to 3I for the components in each step, as shown below.

First, go to step 1. Referring to FIG. 3A, a substrate 210 is provided having a plurality of fingers 211. The substrate 210 can be a printed circuit board (PCB). In this embodiment, the materials of the fingers 211 may be gold (Au) or a copper pad with a gold plated surface. In detail, the fingers 211 are located on both sides of the substrate 210 and outside the wafer setting area of the substrate 210 (the area for setting the wafer).

Go to step 2. As shown in FIG. 3B , a first wafer 220 is disposed on the substrate 210 , and a plurality of first pads 222 are disposed on the active surface 221 of the first wafer 220 . Specifically, the first wafer 220 is aligned with the above-mentioned wafer setting area so as not to cover the fingers 211. Moreover, the active surface 221 of the first wafer 220 faces upward and away from the substrate 210. In this embodiment, the first pads 222 may be disposed at the center of the active surface 221 of the first wafer 220, and the pad material may be selected from aluminum (Al).

Go to step 3. Referring to FIG. 3C, a plurality of first bumps 223 are disposed on the first pads 222 such that the first wafer 220 has conductive terminals protruding from the active surface 221 thereof. In this embodiment, the materials of the first bumps 223 may be selected from gold (Au), or may be copper or nickel gold. The specific setting method of the first bumps 223 may be wire bonding or electroplating.

Perform a preferred step 4. Referring to FIG. 3D, after the first bumps 223 are disposed, the method further includes: covering an insulating coating layer 240 on the active surface 221 of the first wafer 220 and revealing the first portions. The bump 223 is adhered to a tearable viscous flexible sheet 230. More preferably, the insulating coating layer 240 can be a soft rubber layer, so that the temporary fixing can be achieved when the subsequent steps are performed to avoid the tortuous viscous flexible sheet 230 being excessively bent and achieving expansion and contraction. The effect of soldering to bumps.

Go to step 5. Please refer to FIG. 3E, and a schematic diagram of the step is shown in FIG. 4A. The detachable viscous flexible sheet 230 is disposed on the first wafer 220, wherein one of the viscous surfaces 231 of the detachable viscous flexible sheet 230 is adhered to a plurality of flexible inner leads 232. In this embodiment, the flexible inner leads 232 are copper wires, and the outer periphery of the flexible inner leads 232 is covered with a gold layer 232A (please refer to FIG. 5). Therefore, the material cost can be reduced, which is lower than the gold wire used in the previous wire bonding process. More specifically, corresponding to the pad arrangement position and the conductive path to be fanned, the flexible inner leads 232 may be staggered in a comb shape and attached to the adhesive surface 231. In a preferred embodiment, the main system of the tearable flexible flexible sheet 230 can be a UV adhesive film 233, so that the tearable flexible flexible sheet 230 can be further ultraviolet after completing the subsequent steps. The light irradiation method reduces the adhesion of the UV adhesive film 233 to the flexible inner leads 232. In detail, the tearable adhesive flexible sheet 230 is composed of the UV adhesive film 233 and the flexible inner leads 232, and in this step, the UV adhesive film can be used. 233 has an adhesive force, and the tearable adhesive flexible sheet 230 is adhered to the insulating coating layer 240, so that the flexible inner leads 232 can be aligned with the first bumps 223 and the one. The fingers 211 prevent the flexible inner leads 232 from being displaced during the subsequent soldering of the electrical connections. In addition, since the tearable flexible flexible sheet 230 can be flatly attached to the insulating coating layer 240 and is viscous, it is possible to replace the bonding wires to eliminate the arc and pre-fix the flexible internal leads. The position of the foot 232, when applied to a multi-wafer stack, can reduce the wafer stack gap and is less likely to generate bubbles within the wafer stack gap.

Go to step 6. Please refer to FIG. 3F, and please refer to FIG. 4B for a schematic perspective view of the step. In the first pressure welding step, the inner end of the flexible inner leads 232 and the first bumps 223 are aligned and pressure and temperature are applied by a bonding tool 10 (bond tool). The flexible inner leads 232 are bonded to the first bumps 223. In this embodiment, the pressure bonding tool 10 can be a small-to-point small-sized thermal head, or a rectangular pressing block that internally welds the inner ends of all the flexible inner pins 232.

Go to step 7. Please refer to FIG. 3G, and please refer to FIG. 4C for a schematic perspective view of the step. In the second pressure welding step, the pressure welding tool 10 is used to align the outer ends of the flexible inner pins 232 with the fingers 211 and apply pressure and temperature to make the A flexible inner lead 232 is bonded to the fingers 211. After the step is completed, the flexible inner leads 232 have turned on the first bumps 223 and the contacts 211, that is, the first wafer 220 and the substrate 210 have been electrically connected. relationship. In this embodiment, when the pressure bonding tool 10 is pressure-welded to the flexible inner leads 232, it is not necessary to cut off the two ends of the flexible inner pins 232, compared with the conventional inner pins. In the bonding technique, the flexible inner leads 232 are less likely to have displacement problems to accurately connect the first bumps 223 and the fingers 211.

In a preferred embodiment, as shown in FIG. 3H, a schematic perspective view of the step is illustrated in reference to FIG. 4D. The viscous flexible flexible sheet 230 can be irradiated with ultraviolet light by a UV light illuminator 20 to make the UV adhesive film 233 less adhesive and to be easily peeled off from the flexible inner leads 232.

After that, go to step 8. Please refer to FIG. 3I, and please refer to FIG. 4E for a schematic perspective view of the step. The flexible viscous flexible sheet 230 is peeled off to leave the flexible inner leads 232 between the first wafer 220 and the substrate 210, without any conventional arcing height. More specifically, this step removes the stripped UV-adhesive film 233 leaving only the flexible inner leads 232. After the step is completed, the electrical connection between the first wafer 220 and the substrate 210 is achieved without the arcing height, and the overall package height can be reduced.

Preferably, the first bumps 222 of the first wafer 220 are used to implant the first bumps 223, and the insulating coating layer 240 is coated to prevent the flexible inner leads 232 from touching. The active surface 221 of the first wafer 220 causes a short circuit. The present invention utilizes the tearable flexible flexible sheet 230 to adhere to the insulating coating layer 240 (or can directly adhere to the active surface of the first wafer) to temporarily position the flexible inner leads 232 as one of the technologies. Means can completely eliminate the problem of the previous line, and it is not necessary to worry about the risk of causing line collapse and contact with the chip. It can be applied to fine-pitch and replace complex or long wire-bonding process, which improves the package capability. With reliability. Here, the so-called "small line pitch", that is, the pitch of the pitch, generally means that the inner end of the flexible inner leads 232 is spaced below 50 micrometers (μm). Since the effect of replacing the bonding wires to eliminate the line arc can be achieved, especially when applied to multi-wafer stacking, the wafer stacking gap can be reduced, and bubbles are not easily generated in the wafer stacking gap. Therefore, more wafers can be stacked with the same package thickness as conventional to achieve a higher performance package. In addition, the present invention replaces the conventional wire bonding process with the above-mentioned special inner lead bonding (ILB), thereby further improving the overall packaging process efficiency.

The present invention also discloses that the tear-off viscous flexible board used in the foregoing method is illustrated in FIG. A detachable viscous flexible board 230 is suitable for electrical connection of a semiconductor package. One of the viscous surfaces 231 of the detachable viscous flexible board 230 is adhered with a plurality of flexible inner leads 232. The main system of the viscous flexible sheet 230 is a UV adhesive film 233. In detail, the flexible inner leads 232 can be copper wires, and the outer periphery of the flexible inner leads 232 is covered with a gold layer 232A (as shown in FIG. 5), so that the conventional Material cost of using (gold) wire.

According to the second embodiment of the present invention, the method disclosed in the first embodiment is mainly applied and the electrical connection method of the multi-wafer stack is further achieved, which is illustrated in FIGS. 6A to 6G. In this embodiment, the disclosed steps are continued after the first embodiment, so that the first wafer 220 and the substrate 210 have been electrically connected by the flexible inner leads 232. The same elements as those in the first embodiment will be denoted by the same reference numerals and will not be described in detail.

First, as shown in FIG. 6A, a second wafer 350 may be disposed on the first wafer 220, and formed on the first wafer 220 and the second by a Film Over Wire (FOW) 360. The first wafer 220 and the second wafer 350 are bonded between the wafers 350 and partially covered by the flexible inner leads 232. In this embodiment, the first wafer 220 and the second wafer 350 can have the same size and function, and the active surface 351 of the second wafer 350 is provided with a plurality of second pads 352. In the process of the die-bonding, since the flexible inner leads 232 do not have the arcing height as in the conventional bonding wire, the covering tape layer 360 is not too thick and can be thinned, in addition to reducing the amount of material used. In addition, the overall package height can be reduced.

As shown in FIG. 6B, a plurality of second bumps 353 are disposed on the second pads 352. In this embodiment, the materials of the second bumps 353 may be selected from gold (Au). As shown in FIG. 6C, after the second bumps 353 are disposed, a second insulating coating layer 380 may be additionally disposed on the active surface 351 of the second wafer 350 to expose the second bumps 353. For adhesion of a second tearable flexible board 370. In this embodiment, the second insulating coating layer 380 and the insulating coating layer 240 may be a spacer for protecting the active surface 351 of the second wafer 350 and the first wafer 220, respectively. The active surface 221 prevents the occurrence of a short circuit.

As shown in FIG. 6D, the second tearable flexible flexible sheet 370 is disposed on the second wafer 350, wherein one of the adhesive surfaces 371 of the second tearable flexible flexible sheet 370 is adhered to the plurality of Second flexible inner lead 372. When disposed, the second tearable flexible flexible sheet 370 can be more adhered to the second insulating coating layer 380.

As shown in FIG. 6E, a third pressure welding step is performed by the bonding tool 10 to bond the second flexible inner leads 372 to the second bumps 353. As shown in FIG. 6F, a fourth pressure welding step is performed by the bonding tool 10 to bond the second flexible inner leads 372 to the fingers 211. After the above pressure welding step is completed, it indicates that the second wafer 350 and the substrate 210 have reached an electrical connection relationship.

As shown in FIG. 6G, the second flexible adhesive flexible sheet 370 is peeled off to leave the second flexible inner leads 372 between the second wafer 350 and the substrate 210. In a preferred embodiment, the second tear-off viscous flexible board 370 may be further irradiated by ultraviolet light after the two pressure-bonding steps and before the second tear-off viscous flexible board 370 is peeled off. The adhesion of the second flexible inner pins 372 is such that the second tearable flexible flexible sheets 370 are peeled off from the second flexible inner leads 372. In another variant embodiment, the above steps can be repeated to achieve more layer wafer stacking to improve product performance.

According to a third embodiment of the present invention, another method of electrically connecting a semiconductor package is illustrated in FIGS. 7A and 7B. The same elements as those in the first embodiment will be denoted by the same reference numerals and will not be described in detail.

In this embodiment, as shown in FIG. 7A, the viscous surface 231 of the tear-off viscous flexible board 430 is adhered to the flexible inner leads 232, and a pin bus 434 is adhered, and The pin bus bar 434 has at least one extension pin 434A that is juxtaposed with the inner ends of the flexible inner pins 232. In other words, the pin bus bar 434 and the flexible inner pins 232 can be adhered to the same surface (ie, the viscous surface 231). In detail, the flexible inner pins 232 can include a plurality of first side inner pins 432A and a plurality of second side inner pins 432B fanned in different directions, and the pin bus bar 434 can be Passing through the gap between the first side inner pin 432A and the second side inner pins 432B. The tearable flexible flexible sheet 430 can be disposed on a wafer 420. As shown in FIG. 7B, the active surface 221 of the wafer 420 is provided with a plurality of centrally arranged pads 222, which may be composed of a plurality of first row pads 422A and a plurality of second row pads 422B. The inner end of the first side inner lead 432A can be aligned with the first row of solder pads 422A, and the second side is disposed when the tearable adhesive flexible sheet 430 is disposed on the wafer 420. The inner end of the pin 432B is aligned with the second row of pads 422B for pressure bonding. In this embodiment, the pin bus bar 434 is located in the arrangement gap between the first row of pads 422A and the second row of pads 422B. The extension pins 434A can be aligned with one of them. The second row of pads 422B can be used as a ground or power connection.

The above is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. Although the present invention has been disclosed in the above preferred embodiments, it is not intended to limit the present invention. Any simple modifications, equivalent changes and modifications made without departing from the technical scope of the present invention are still within the technical scope of the present invention.

Step 1 provides a substrate

Step 2 Set a wafer on the substrate

Step 3 Set the bump on the pad of the wafer.

Step 4 Cover the active surface of the insulating coating layer on the wafer

Step 5 Set the tear-off viscous soft board on the wafer

Step 6 Perform the first pressure welding

Step 7 Perform a second pressure welding

Step 8 tear off the tearable flexible board

10. . . Pressure welding tool

20. . . UV light illuminator

110. . . Substrate

111. . . Finger

120. . . First wafer

121. . . Active surface

122. . . First pad

130. . . First wire bond

150. . . Second chip

151. . . Active surface

152. . . Second pad

160. . . Overlay layer

170. . . Second wire

210. . . Substrate

211. . . Finger

220. . . First wafer

221. . . Active surface

222. . . First pad

223. . . First bump

230. . . Tearable flexible board

231. . . Viscous surface

232. . . Flexible inner pin

232A. . . Gold layer

233. . . UV adhesive film

240. . . Insulating coating

350. . . Second chip

351. . . Active surface

352. . . Second pad

353. . . Second bump

360. . . Overlay layer

370. . . Second tearable flexible board

371. . . Viscous surface

372. . . Flexible inner pin

372A. . . Gold layer

380. . . Second insulating coating layer

420. . . Wafer

422A. . . First row of pads

422B. . . Second row of pads

430. . . Tearable flexible board

432A. . . First side inner pin

432B. . . Second side inner pin

434. . . Pin bus

434A. . . Extension pin

Figure 1: Schematic cross-sectional view of a conventional wafer stack structure using wire bonding.

2 is a flow block diagram showing an electrical connection method of a semiconductor package in accordance with a first embodiment of the present invention.

3A to 3I are schematic cross-sectional views showing the components of the electrical connection method of the semiconductor package in accordance with the first embodiment of the present invention.

4A to 4E are schematic perspective views of the components of the 3E to 3I drawings in the process according to the first embodiment of the present invention.

FIG. 5 is a partially enlarged cross-sectional view showing the electrical connection method of the semiconductor package according to the first embodiment of the present invention.

6A to 6G are schematic cross-sectional views showing the components of the semiconductor package according to the second embodiment of the present invention when multi-wafer stacking is performed.

7A and 7B are views of a bottom view of another tear-off viscous flexible sheet according to a third embodiment of the present invention and an upper view of the attached wafer.

210. . . Substrate

211. . . Finger

220. . . First wafer

221. . . Active surface

222. . . First pad

223. . . First bump

230. . . Tearable flexible board

231. . . Viscous surface

232. . . Flexible inner pin

233. . . UV adhesive film

240. . . Insulating coating

Claims (16)

An electrical connection method for a semiconductor package, comprising: providing a substrate having a plurality of fingers; providing a first wafer on the substrate, and providing a plurality of first pads on an active surface of the first wafer; a plurality of first bumps are disposed on the first pads; a tear-off adhesive soft plate is disposed on the first wafer, wherein one of the adhesive surfaces of the tearable flexible flexible board is adhered to the plurality of a flexible inner lead; performing a first pressure welding step to bond the flexible inner leads to the first bumps; performing a second pressure welding step to make the flexible inner portions Leading the contacts to the fingers; and tearing away the tear-off viscous flexible sheet to leave the flexible inner leads between the first wafer and the substrate. According to the electrical connection method of the semiconductor package of claim 1, after the first bumps are disposed and before the tearable adhesive flexible board is disposed, the method further comprises: covering an insulating coating layer The active surface of the first wafer exposes the first bumps for adhesion of the tearable viscous flexible board, and the insulating coating layer is a soft rubber layer. The electrical connection method of the semiconductor package according to claim 1, wherein the main system of the tearable flexible flexible board is a UV adhesive film, and after the two pressure welding steps, the ultraviolet light is irradiated. The adhesion of the UV adhesive film to the flexible inner leads is reduced. The method of electrically connecting a semiconductor package according to claim 1, wherein the flexible inner leads are copper wires, and the outer edges of the flexible inner leads are covered with a gold layer. The method of electrically connecting a semiconductor package according to claim 1, wherein the first pads are disposed in a center of the active surface of the first wafer, and the flexible inner leads are staggered in a comb shape. arrangement. According to the electrical connection method of the semiconductor package of claim 1, the method further comprises: disposing a second wafer on the first wafer, and forming a first adhesive wafer on the first wafer and the first Between the two wafers, the first wafer and the second wafer are bonded and partially covered with the flexible inner leads. The method of electrically connecting a semiconductor package according to claim 6 , wherein the first wafer and the second wafer have the same size and function, and the active surface of the second wafer is provided with a plurality of second pads . According to the electrical connection method of the semiconductor package of claim 7, after the step of disposing the second wafer, the method further comprises the steps of: setting a plurality of second bumps on the second pads; a detachable viscous flexible board is disposed on the second wafer, wherein a viscous surface of the second detachable viscous flexible board is adhered to the plurality of second flexible inner leads; and the third pressing is performed a soldering step of bonding the second flexible inner leads to the second bumps; performing a fourth pressure bonding step to bond the second flexible inner leads to the contacts And tearing off the second tear-off viscous flexible sheet to leave the second flexible inner leads between the second wafer and the substrate. According to the electrical connection method of the semiconductor package of claim 7, after the second bumps are disposed and before the second tear-off flexible flexible board is disposed, the method further comprises: covering a second insulation Coating a layer on the active surface of the second wafer and revealing the second bumps for adhesion of the second tearable viscous flexible board. The method of electrically connecting a semiconductor package according to claim 1, wherein the adhesive surface is further adhered to a pin bus bar, the pin bus bar having at least one extension pin, and the plurality of flexible pins The inner ends of the pins are side by side. The method of electrically connecting a semiconductor package according to claim 10, wherein the flexible inner leads comprise a plurality of first side inner pins and a plurality of second side inner pins fanned in different directions. The pin bus bar passes through a gap between the first side inner pin and the second side inner pins. According to the electrical connection method of the semiconductor package of claim 11, wherein the first pads are composed of a plurality of first row pads and a plurality of second row pads, when the tearability is When the first board is disposed on the first chip, the inner ends of the first side inner pins are aligned with the first row of pads, and the inner ends of the second side inner pins are aligned with the Some second row of pads. A tearable flexible flexible board suitable for electrical connection of a semiconductor package, wherein a viscous surface of the tearable flexible flexible board is adhered with a plurality of flexible inner leads, and the tearable softness is soft The main system of the board is a UV adhesive film. The tear-off viscous flexible board according to claim 13 , wherein the flexible inner leads are copper wires, and the outer edges of the flexible inner leads are covered with a gold layer. The tear-off viscous flexible board according to claim 13 , wherein the adhesive surface is further adhered to a pin bus bar, the pin bus bar has at least one extension pin, and the flexible inner portion The inner ends of the pins are side by side. The tear-off viscous flexible board according to claim 15 , wherein the flexible inner leads comprise a plurality of first side inner pins and a plurality of second side inner pins fanned in different directions The pin bus bar passes through a gap between the first side inner pin and the second side inner pins.