JPH06275676A - Semiconductor device and electronic device with built-in semiconductor device - Google Patents

Abstract

(57) [Summary] [Purpose] To provide a semiconductor device with a high mounting yield, which can have a narrow lead pitch and a large number of pins. A semiconductor device is provided on a package 2, a flexible and insulating film 3 extending inside and outside the package 2, and provided on at least one surface of the film 3 and the package 2 Conductive Au bumps 9 and 5 that extend inside and outside of the
A semiconductor chip 1 which is provided in the package 2 and is connected to electrodes 13 via Au bumps 9 at the inner ends of the leads 4 and a plurality of leads 4 made of a conductor layer provided with
It consists of 2. Since the leads 4 are formed by etching the conductor layer provided on the film 3, the lead pitch can be narrowed and the number of pins can be increased. The film is flexible, and the outer ends of the leads can be brought into close contact with the wiring layer of the wiring board, improving the mounting yield.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device and an electronic device incorporating the semiconductor device.

[0002]

2. Description of the Related Art Electronic devices are required to have high-density mounting in terms of functions, and to be lightweight, compact, and thin in terms of mounting. Further, in order to reduce the manufacturing cost of electronic components, a resin-encapsulated (resin package) type semiconductor device, which is cheap in material and good in productivity, is widely used as a package form. Known resin package type semiconductor devices include those using a metal lead frame, TCP (Tape Carrier Packageng) in which leads are formed on the surface of an insulating film, and the like.

A semiconductor device using a lead frame is described in "Hitachi Kenron", No. 3, 1992, issued by Hitachi Hyoronsha, and issued on March 25, 1992, P75 to P80. This document describes TSO as a smaller and thinner package.
P (Thin Small Outline Package), SSOP (Shrink
Small Outline Package), TQFP (Thin Quad Flat)
Package), STZIP (Shrink Thin Zigzag Inline
Package) is disclosed. In addition, SOP (Small Outli
The ne Package) has outer leads arranged on two sides of the package, and the QFP (Thin Quad Flat Package) has outer leads arranged on the four sides of the package.
Further, in TSOP and TQFP, the lead pitch size is narrowed to 0.5 mm and the package body thickness is thinned to 1 mm. These semiconductor devices are mounted on the board by soldering.

The processing limits of metal lead frames are described in "Nikkei Microdevice", August 1988 issue, Nikkei BP, August 54, 1988, P54-P60. This document describes that the press limit of the lead frame is about 0.2 mm.

Surface mounting is described in "Nikkei Electronics," issued by Nikkei BP, March 19, 1990 (No. 495), P119 to P136. In this document, as a package form of a multi-terminal / narrow-pitch LSI, a plastic flat package such as plastic or plastic SOP, TAB (Tape Automated Bonding) as a tape carrier package (TCP), and transfer mold as a tape carrier package. There is a mold TAB by, and the outer leads in these LSI packages have a narrower pitch of 0.3 mm to 0.2 m.
It is described that it is shifting to m. In addition, in this document, "in order to prevent the outer leads from bending and the outer leads not being connected to the printed wiring board due to the looseness of the outer leads, the LSI manufacturer ships without disconnecting the outer leads. The outer leads are molded and mounted directly. "

[0006] In addition, "Nikkei Microdevice" issued by Nikkei BP, February 1991 issue, February 1, the same year, P65, T
A thin package (Paper Thin Packag) in which the thickness of the package is 0.5 mm by transfer molding AB.
e) is introduced. In this package, the Cu lead supported by the polyimide tape extending inside and outside the package extends independently from the polyimide tape outside the package and bends to have a gull wing structure.

On the other hand, an example in which bumps for connecting the electrodes of the semiconductor chip and the leads in the TAB are provided on the tape carrier is, for example, "Nikkei Microdevice" issued by Nikkei BP, March 1986 issue, March 1 of the same year. Issued daily, P128 to P135
It is described in. Also, "Electronic Materials Separate Volume" issued by the Industrial Research Group, December 10, 1988, P105 to P113, describes inner lead bonder and outer lead bonder. Further, this document also describes a bumper bonder and an example of forming balls on a wafer by capillaries.

On the other hand, as a technique for forming bumps on a semiconductor chip, for example, "FUJI" issued by Fujitsu Limited.
TSU ", November 1992, P773 to P778, discloses an example in which a stud bump made of gold (Au) is formed on a semiconductor chip by using a gold wire. In addition, Nikkei BP's "Nikkei Micro Device" September 1989 issue, September 1 of the same year
An example of forming bumps with solder wires is disclosed in P15, issued daily.

[0009]

Due to the demand for lighter, thinner, shorter and smaller semiconductor devices, the lead pitch is becoming narrower and the lead width is becoming narrower. In addition, the number of leads (the number of pins) is increasing due to the multi-functionalization. In the case of a semiconductor device using a metal lead frame, the lead frame is thinner, and the lead pitch and lead width are also smaller. However, the thinning of the lead frame and the narrowing of the lead width and the lead pitch lead to a decrease in the mechanical strength of the leads, and the frequency of shorts between the leads due to lead deformation increases. Further, in the structure in which the electrodes of the semiconductor chip are connected to the leads by wire bonding, there is a limit to the diameter reduction of the wire in order to prevent the wire from hanging down. There is also a limit to the reduction of. For this reason, restrictions naturally occur in reducing the chip shrink (small size).

In a TAB such as TCP or molded TCP, since a copper foil or the like is attached to an insulating tape (film) and the copper foil is etched to form a lead, a metal lead is used. Compared to the frame, the lead pitch can be reduced and the lead width can be narrowed, and the number of pins can be increased easily. However, even in this TAB technique, the leads are thin and thin, so that the leads are easily deformed, and a short circuit between the leads is likely to occur. Further, the leads are connected to the wiring board by solder, but the solder melted by the temperature at the time of connection flows out to the adjacent terminals and comes into contact therewith, so that a so-called solder bridge occurs. Therefore, the collective connection method using reflow, infrared heating, or the like becomes difficult to apply when the lead pitch is narrowed, resulting in individual connection.

An object of the present invention is to reduce the lead pitch,
An object of the present invention is to provide a semiconductor device which can achieve a high number of pins, has a high mounting yield, and is easy to mount. The above and other objects and novel features of the present invention will be apparent from the description of the present specification and the accompanying drawings.

[0012]

The outline of the representative ones of the inventions disclosed in the present application will be briefly described as follows. That is, the semiconductor device of the present invention is
Appearance is composed of a package and a flexible and insulating film extending inside and outside the package. On one surface of the film, a plurality of leads made of a conductor layer extending inside and outside the package are provided. The leads are formed by etching the conductor layer formed on the film. Further, the inner ends of the leads are electrically connected to the bump base conductor layer provided on the other surface of the film through the conductor filled in the through holes. Au bumps are formed on the bump base conductor layer and the outer ends of the leads, respectively. A semiconductor chip is arranged in the package, and electrodes of the semiconductor chip are electrically connected to Au bumps on the inner end side of the lead. The film is provided with a notch for separating desired leads, and each film protruding from the package is independently deformable. The Au bumps are formed by directly crimping and cutting the Au wires onto the leads. In mounting, the film extending from the package is bent so that the outer ends of the leads are superposed on the wiring layer of the desired wiring board and ultrasonic vibration is applied to connect the bumps to the wiring layer.

In the electronic device of the present invention comprising the wiring board and the semiconductor device mounted on the mounting surface of the wiring board, the wiring boards have a plurality of mountings extending at a predetermined angle from each other. The semiconductor device has a surface, a package, a flexible and insulative film extending inside and outside the package, and provided on at least one surface of the film and inside and outside the package. A plurality of leads, each of which is formed of a conductor layer and which has conductive bumps provided on its inner and outer end portions, and a semiconductor which is provided in the package and whose electrodes are connected via the bumps at the inner ends of the leads. A lead having a chip and a notch provided in the film so as to separate desired leads from each other, and the lead supported by each film of the semiconductor device is a lead. It is attached separately to a plurality of mounting surfaces of the wiring board because it is deformable for each film. That is, some of the leads are mounted on the mounting surface of the main surface of the wiring board, and the other leads are mounted on the mounting surface of the wiring board perpendicular to the main surface of the wiring board.

[0014]

According to the above-mentioned means, in the semiconductor device of the present invention, since the leads are structured to be attached to the film, even if the leads are thin and thin, they are not deformed independently. The occurrence of short circuit between leads can be suppressed.

In the semiconductor device of the present invention, since the outer ends of the leads are supported by the film and are connected to the wiring layer of the wiring substrate by ultrasonic vibration, the Au bumps are less deformed and the Au bumps are less deformed. Thus, it is possible to prevent the occurrence of defects such as touching an adjacent wiring layer.

In the semiconductor device of the present invention, since the leads are supported by the flexible film, even when the Au bumps are pressure-bonded to the wiring layer of the wiring board, even if the wiring board surface has irregularities or undulations. It surely adheres to the wiring layer and improves the yield of mounting.

In the semiconductor device of the present invention, the Au bumps formed for mounting are directly formed on the leads, and it is not necessary to plate the leads as in the conventional case. Therefore, the cost for forming Au bumps can be reduced. Is possible.

In the semiconductor device of the present invention, since the leads have a structure in which the conductor layer formed on the film is formed by etching, the lead width and lead pitch can be narrowed and the number of pins is increased. Can also be achieved.

In the semiconductor device of the present invention, since the leads have a structure in which the conductor layer formed on the film is formed by etching, the lead width and lead pitch can be narrowed, and the semiconductor chip can be made compact. And miniaturization of the package can be achieved.

In the electronic device of the present invention, the leads extending from the package of the semiconductor device and supported by the respective films are provided with respect to the wiring board having a plurality of mounting surfaces extending at a predetermined angle to each other. , Some of the leads are mounted on one mounting surface, the remaining leads are mounted on the mounting surface perpendicular to the mounting surface, the mounting is three-dimensional,
Mounting efficiency is improved.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. 1 is a cross-sectional view showing a main part of a semiconductor device according to an embodiment of the present invention, FIG. 2 is a plan view of a film used for manufacturing the semiconductor device of the present invention, and FIG. 3 is a bottom view thereof.
4 is an enlarged sectional view of a part of the film, FIG. 5 is a plan view of a semiconductor chip incorporated in the semiconductor device of the present invention,
FIG. 6 is a partially enlarged sectional view showing a connection state between electrodes of a semiconductor chip and inner ends of leads supported by a film in the semiconductor device of the present invention, and FIG. 7 is a schematic diagram showing a mounted state of the semiconductor device of the present invention. FIG. 8 is a schematic sectional view showing a mounting structure of a semiconductor device of the present invention.

A semiconductor device 1 of the present invention, as shown in FIG. 1, is a package 2 made of a resin having a rectangular appearance.
And a film 3 extending from each of the four sides around the package 2. On the lower surface of the film 3 (see FIG. 1), a plurality of leads 4 made of a conductor layer are provided. As shown in FIG. 2, the leads 4 extend radially inside and outside the package 2 and have A at the outer end.
The u-bump 5 (a portion where dots are applied) is provided.
The outer end of the lead 4 provided with the Au bump 5 also serves as the outer end of the film 3.

A central portion of the film 3 is punched out in a rectangular shape to form a hole 6. The inner end of the lead 4 extends to the edge of the hole 6. Further, as shown in FIGS. 4 and 6, a bump underlayer conductor layer 7 is provided around the hole 6 on the side where the leads 4 are not provided, and Au is formed on the bump underlayer conductor layer 7. Bump 9
(See FIG. 3) are provided. As shown in FIG. 4, a through hole 10 is provided in the central film portion of the bump base conductor layer 7. The through hole 10 penetrates the center of the inner end portion of the lead 4. A conductor 11 is filled in the through hole 10.
Therefore, the inner end of each lead 4 and the bump foundation conductor layer 7
And are electrically connected by a conductor 11.

As shown in FIG. 5, the semiconductor chip 12 sealed in the package 2 has a plurality of electrodes 13 along the peripheral edge on one surface side. These electrodes 13 are the Au
Corresponding to the bump 9, and as shown in FIG. 6, it is electrically connected to the Au bump 9.

Next, manufacturing of such a semiconductor device 1 will be described. In manufacturing the semiconductor device 1, FIG.
~ A film 3 as shown in Fig. 4 is prepared. The film 3 is made of an insulating polyester resin having a thickness of 20 to 30 μm and is a rectangular body having rectangular cutouts 15 at four corners. The rectangular portion indicated by the alternate long and short dash line having the apex of the tip of each notch 15 as the apex is the region forming the package 2. Therefore, the film portion projects in a rectangular shape from the four sides of this package 2 (for convenience of explanation, this film portion is projected and the film portion 1 is projected.
6). A rectangular hole 6 is provided in the center of the film 3. The hole 6 is smaller than the semiconductor chip 12.

As shown in FIG. 2, on one surface of the film 3, the leads 4 extend radially from the peripheral edge of the hole 6 to the outer edge of the film portion 16. The lead 4 is made of copper foil having a thickness of about 35 μm attached to one surface of the film 3 or copper produced by rotary printing.
The printed layer having a thickness of 0 μm is formed by etching. In this example, four leads 4 are provided from the four sides of the rectangular hole 6 to the edges of the film portion 16. The pitch of the inner ends of the leads 4 corresponds to the pitch of the electrodes 13 of the semiconductor chip 12. The pitch of the outer ends of the leads 4 corresponds to the pitch of the wiring layer (footprint or the like) on the wiring board when the semiconductor device 1 is mounted, and is wider than the pitch of the electrodes 13 of the semiconductor chip 12. . In addition, at the outer end of the lead 4,
Au bumps 5 are provided as shown in FIG. The Au bump is formed by spheroidizing the tip of an Au wire having a diameter of 20 to 25 μm by electric discharge or the like, and then directly crimping and breaking the lead 4 to the lead 4.

A bump base conductor layer 7 is formed around the hole 6 on the other surface of the film 3, that is, the surface on which the leads 4 are not provided. The bump base conductor layer 7 is formed by etching a layer made of copper provided on the surface of the film 3 similarly to the formation of the leads 4, and its size is
For example, it is 50 to 80 μm □. The bump base conductor layer 7 corresponds to the electrode 13 of the semiconductor chip 12 and faces the inner end of the lead 4 provided on the back surface as shown in FIG. A through hole 10 is formed in the film portion corresponding to the center of the bump base conductor layer 7. The through hole 10 penetrates the center of the inner end portion of the lead 4. A conductor 11 is filled in the through hole 10 to electrically connect the lead 4 and the bump base conductor layer 7. An Au bump 9 is formed on the bump base conductor layer 7. The Au bumps 9 are formed by the same method as the Au bumps 5. FIG. 3 shows Au bumps 9 arranged on the periphery of the holes 6 of the film 3.

With respect to such a film 3, as shown in FIG. 2, the semiconductor chip 12 is indicated by a chain double-dashed line.
Are positioned and stacked, and the electrodes 13 of the semiconductor chip 12 are
The Au bumps 9 on the inner end side of the leads 4 are connected to each other by ultrasonic vibration. Since the Au bump 9 is rubbed and connected to the electrode 13 by ultrasonic vibration, the Au bump 9 does not melt and come into contact with the adjacent electrode 13.
Thereafter, as shown by the alternate long and short dash line in FIG. 2, the package 2 is formed by conventional transfer molding, and the semiconductor device 1 as shown in FIG. 1 is manufactured.

Such a semiconductor device 1 has a flat structure in which the leads 4 extend straight as shown in FIG.
Alternatively, as shown in FIG. 7, the lead 4 is sold in a gull wing structure in which it is bent in a one-step step. This semiconductor device 1 is mounted by connecting the outer ends of the leads 4 to the wiring layer 21 of the wiring substrate 20, as shown in FIG. 7, like a general semiconductor device. However, in the case of the semiconductor device 1 of the present invention, the lead 4 is connected to the wiring layer 21 by ultrasonic vibration. That is, the Au bump 9 portion at the outer end of the lead 4 is rubbed and connected to the wiring layer 21 by the ultrasonic vibration of the tool pressed from above the film 3. Therefore, unlike the conventional reflow, the entire solder that is the connection body does not melt out, and a defect such as a solder bridge between adjacent leads does not occur. At the time of this mounting, the outer ends of the leads 4 are made of the flexible film 3
Therefore, even if the surface of the wiring substrate 20 has irregularities or undulations, the Au bumps 5 of the leads 4 are reliably pressed against the wiring layer 21 and the bondability becomes good. Note that, in FIG. 7, the leads 4 and the conductors 11 provided on the surface of the film 3 are indicated by thick lines.

Since the semiconductor device 1 of the present invention has a structure in which the leads 4 are supported by the flexible film 3, as shown in FIG. 8, a horizontally extending wiring substrate extending in the horizontal direction. The leads 4 can be connected to the vertical extension wiring board 31 extending vertically to the horizontal extension wiring board 30. As a result, three-dimensional mounting is also possible, and the mounting margin is improved. In FIG. 8, the semiconductor device 35 on the left side is a conventional TSOP. Further, in FIG. 8, the leads 4 provided on the surface of the film 3 are indicated by thick lines.

[0031]

【The invention's effect】

(1) In the semiconductor device of the present invention, since the entire portion including the inner and outer ends of the leads is supported by the film, the leads can be formed even if the leads are thin and thin or the lead pitch is small. It is possible to obtain an effect that defects such as deformation and contact with adjacent leads do not occur.

(2) In the semiconductor device of the present invention, since the outer ends of the leads are supported by the film and are connected to the wiring layer of the wiring board by ultrasonic vibration, the Au bumps have a small deformation amount. , Au bumps can prevent the occurrence of defects such as contact with an adjacent wiring layer.

(3) In the semiconductor device of the present invention, since the leads are supported by the flexible film, when the Au bumps are pressure-bonded to the wiring layer of the wiring board, unevenness or waviness is generated on the wiring board surface. Even if there is, the effect of reliably adhering to the wiring layer and improving the mounting yield can be obtained.

(4) In the semiconductor device of the present invention, the Au bumps formed for mounting are directly formed on the leads, and it is not necessary to plate the leads as in the conventional case. The effect that the cost can be reduced can be obtained.

(5) In the semiconductor device of the present invention, since the leads are formed by etching the conductor layer formed on the film, the lead width and lead pitch can be narrowed, and The effect that multiple pins can be achieved can be obtained.

(6) In the semiconductor device of the present invention, since the leads have a structure in which the conductor layer formed on the film is formed by etching, the lead width and lead pitch can be narrowed, and the semiconductor The effect that the miniaturization of the chip and the miniaturization of the package can be achieved is obtained.

(7) In the electronic device of the present invention, the wiring substrate having a plurality of mounting surfaces extending at a predetermined angle to each other extends from the package of the semiconductor device and is supported by each film. Some of the leads are attached to one mounting surface and the remaining leads are attached to a mounting surface perpendicular to the mounting surface, so that the mounting becomes three-dimensional and the mounting efficiency is improved. The effect is obtained.

(8) In the semiconductor device of the present invention, the film supporting the leads is formed of an inexpensive polyester resin, so that the effect of cost reduction can be achieved.

(9) Due to the above (1) to (8), according to the present invention, the lead pitch can be narrowed and the number of pins can be increased, and the mounting yield is high, and the mounting is easy and the three-dimensional mounting is inexpensive. The synergistic effect that a possible semiconductor device can be provided is obtained.

Although the invention made by the present inventor has been specifically described based on the embodiments, the present invention is not limited to the above embodiments, and various modifications can be made without departing from the scope of the invention. Needless to say, for example,
In the above-mentioned embodiment, the Au bumps at the inner and outer ends of the lead are separately provided on the front and back sides of the film. However, the lead is provided on one side of the film, and the Au bumps are provided on the inner and outer ends of the lead. Even if the Au bumps at the ends are provided on the same surface side of the film, the same effect as in the above embodiment can be obtained. Further, if the film and the package are made of the same material, for example, an epoxy resin, peeling due to a difference in thermal expansion coefficient between the film and the package does not occur,
The reliability of the package can be increased. Further, in the case of a semiconductor device having a structure in which the leads extend from both sides of the package, the film has a shape extending from both sides of the package, so that the notch is not necessary. Further, in the above embodiment, the inner and outer ends of the lead are aligned with the inner and outer ends of the film, but the inner and outer ends of the lead may be located inside the film end. Further, the bumps provided on the inner and outer ends of the leads may be solder bumps formed of solder wires.

In the above description, the case where the invention made by the present inventor is mainly applied to the manufacturing technology of the surface mount type semiconductor device which is the field of application which is the background of the invention has been described, but the invention is not limited thereto. The present invention can be applied to a semiconductor device having a structure in which leads are supported by an insulating film and a mounting structure (electronic device) thereof.

[Brief description of drawings]

FIG. 1 is a sectional view showing a main part of a semiconductor device according to an embodiment of the present invention.

FIG. 2 is a plan view of a film used for manufacturing the semiconductor device of the present invention.

FIG. 3 is a bottom view of a film used for manufacturing the semiconductor device of the present invention.

FIG. 4 is an enlarged cross-sectional view of a part of a film used for manufacturing the semiconductor device of the present invention.

FIG. 5 is a plan view of a semiconductor chip incorporated in the semiconductor device of the present invention.

FIG. 6 is a partial enlarged cross-sectional view showing a connection state between an electrode of a semiconductor chip and an inner end of a lead supported by a film in a semiconductor device of the present invention.

FIG. 7 is a schematic cross-sectional view showing a mounted state of the semiconductor device of the present invention.

FIG. 8 is a schematic cross-sectional view showing a mounting structure of a semiconductor device according to the present invention.

[Explanation of symbols]

1 ... Semiconductor device, 2 ... Package, 3 ... Film, 4 ...
Leads, 5 ... Au bumps, 6 ... Holes, 7 ... Bump base conductor layer, 9 ... Au bumps, 10 ... Through holes, 11 ... Conductors, 12 ... Semiconductor chips, 13 ... Electrodes, 15 ... Cut portions,
16 ... Overhanging film portion, 20 ... Wiring board, 21 ...
Wiring layer, 30 ... Horizontally extending wiring board, 31 ... Vertically extending wiring board, 35 ... Semiconductor device.

Claims (5)

[Claims] 1. A package, a flexible and insulating film extending inside and outside the package, and provided on at least one surface of the film and extending inside and outside the package. And a plurality of leads made of a conductor layer having conductive bumps provided at the inner and outer ends thereof, and a semiconductor chip provided in the package and having electrodes connected to each other via the bumps at the inner ends of the leads. A semiconductor device characterized by the above. 2. A package, a flexible and insulating film extending inside and outside the package, and provided on at least one surface of the film and extending inside and outside the package. A plurality of leads made of a conductor layer having conductive bumps on the inner and outer ends thereof, and a semiconductor chip provided in the package and having electrodes connected to each other via the bumps on the inner ends of the leads, And a notch formed in the film so as to separate the leads of the semiconductor device. 3. The semiconductor device according to claim 1, wherein the bump is formed by directly crimping and dividing a wire made of Au or solder to a lead. 4. The semiconductor device according to claim 1, wherein the film and the package are made of the same material. 5. An electronic device comprising a wiring board and a semiconductor device mounted on a mounting surface of the wiring board, wherein the wiring board has a plurality of mounting surfaces extending at a predetermined angle from each other. The semiconductor device has a package, a flexible and insulating film extending inside and outside the package, and provided on at least one surface of the film and extending inside and outside the package. Semiconductor chip having a plurality of leads formed of a conductor layer extending in the vertical direction and provided with conductive bumps at inner and outer end portions, and electrodes provided in the package and connected via bumps at inner ends of the leads And a notch formed in the film so as to separate desired leads from each other, and the leads of the semiconductor device are separately attached to a plurality of mounting surfaces of the wiring board. An electronic device characterized by being provided.