JPH1187386A - Semiconductor device, method of manufacturing the same, and substrate frame - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optimal semiconductor by providing a transfer molding process which is most easily automated, mass-produced, low-priced and highly reliable in a semiconductor device having a resin-sealed semiconductor element mounted on a wiring board. Provided is a method for manufacturing an apparatus and a push-back type substrate frame used in the method. A push-back type substrate frame is provided.
When applying and forming a solder resist on at least the first
A thermosetting resist film 28 is formed in the vicinity of the surface along the pushback line, and a photoresist film 29 is formed in other areas. Further, means (slit) 30 for opposing the wiring board area 33 of the board frame and approaching the push-back line to reduce distortion at the time of push-back.
Is provided. The thermosetting resist hardly causes the whitening phenomenon even when the substrate frame is cut. Pushback processing is quickly performed by the slit.

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 more particularly, to an improved push-back type substrate frame formed of a copper-clad laminate or the like, a semiconductor device using the substrate frame, and a method of manufacturing the same. It is.

[0002]

2. Description of the Related Art Conventionally, semiconductor devices are roughly classified into a non-hermetic sealing type of a plastic type using a resin sealing body and an hermetic sealing type using a package of ceramic or metal. The former is somewhat inferior in reliability, but is more practical than the latter because it is superior in mass productivity and economy. In many resin-sealed semiconductor devices, a metal lead frame and a semiconductor chip mounted thereon are resin-sealed with a mold resin such as an epoxy resin. However, in recent years, printed wiring boards composed of a copper-clad laminate or the like have been used because, for example, the outer leads serving as external extraction electrodes in a lead frame are easily deformed or are not suitable for mounting a plurality of semiconductor elements. (PCB: Printed Circ
After mounting a semiconductor element on this using a wiring board consisting of an insulating substrate such as a uit board, and electrically connecting the connection electrode of the semiconductor element and the wiring part of the wiring board by wire bonding, etc. Techniques for performing technical resin molding have been attempted. This copper-clad laminate is supplied in a state where the wiring board is usually held by a board frame or in the form of individual pieces of the wiring board.

As a method of forming a resin sealing body for packaging a semiconductor element, for example, a potting method and a transfer molding method are known. In the potting method, a fixed amount of a liquid resin such as an epoxy-based or silicone-based resin is dropped from a semiconductor element having a connection electrode electrically fixed to a wiring portion of the wiring board mounted and fixed on the wiring board, This is a method of curing by heating. The resin sealing body molded by this method is expensive and may spread over a region determined at the time of manufacturing. Also,
It is difficult to achieve the desired thickness. The transfer molding method is a method of molding a thermosetting resin, in which a semiconductor element having connection electrodes mounted and fixed on a wiring board and a wiring board on which the semiconductor element is mounted are arranged in a heated mold cavity. Then, a material (thermosetting resin) is press-fitted into the cavity, plasticized and cured, and a resin sealing body is formed.

Referring to FIG. 15, a semiconductor device having a semiconductor element formed by a conventional potting method and supported by a wiring board will be described. The figure is a cross-sectional view of a wiring board on which a semiconductor element is mounted. Wiring board 1 of FIG.
Is a printed wiring board (PC) in which a wiring pattern and connection electrodes (inner leads) are formed on the main surface by molding a copper-clad laminate.
B). The copper-clad laminate is manufactured by impregnating a glass fiber cloth with an epoxy resin and heating the laminated body formed by laminating under pressure. The copper foil formed on the surface of the laminate is etched and formed into a wiring pattern. A plurality of external connection electrodes 3 that are electrically connected to connection electrodes and are electrically connected to external circuits are formed on side surfaces of the wiring board 1. The external connection electrode 3 is composed of a nickel plating layer or a conductive layer in which a gold or solder layer is formed on the nickel plating layer. A connection electrode is also formed on the main surface of the semiconductor element 2, and this connection electrode is electrically connected to the wiring pattern by a bonding wire 4 such as gold or aluminum (Al). The external connection electrode 3 of the wiring board 1 is connected to the wiring pattern, and the external circuit is electrically connected to the semiconductor element 2. This semiconductor element 2
A liquid resin such as an epoxy resin is dropped on the bonding wire 4. The liquid resin is cured to form the resin sealing body 20. In addition, a bump electrode 5 such as solder, which is electrically connected to a connection electrode and electrically connected to an external circuit, is formed on the back surface of the wiring board 1.
(B)) The external connection electrode 3 extending to the inner surface of the through hole formed in the wiring board is electrically connected to the connection electrode on the main surface of the wiring board 1 (FIG. 15).
(C)) and the like are known.

[0005] A semiconductor device using the above-described prior art includes, for example, a chip size package (CSP).
kage). In the prior art, processes such as attaching a semiconductor element to a thin film of a CSP and performing wire bonding and sealing, and processing such as fine wiring on a chip and resin sealing are performed. However, the conventional CSP
Had the following problems. First, in the case of a CSP using a film or the like, reliability may be reduced due to a difference in a coefficient of linear expansion from a wiring board to be mounted. For this reason, as specified in the known literature, a cushion is required to reduce the thermal shock, which is a bottleneck for reducing the price. Further, when this film is used, it is warped or undulated because it is thin, and must be attached to or detached from a special jig, and the process is complicated. In addition, in the important transfer molding process, the operation cannot be performed unless the special jig is removed, which has been a great obstacle to the yield of the transfer and the molding. On the other hand, the method of fine wiring on a chip has a complicated structure and manufacturing method, is not suitable for mass production, and has been an expensive semiconductor device.

In order to solve the problems of reliability and price of the conventional CSP, a heat-resistant double-sided copper-clad laminate subjected to push-back processing is used for a wiring board and resin-sealed by transfer molding to provide a low-cost and high-cost. Reliable small and thin fine pitch semiconductor devices have been developed. That is, a semiconductor device having a wiring board formed by a push-back method, a push-back processing of a substrate frame subjected to wiring processing, plating processing, and external processing on a heat-resistant double-sided copper-clad laminate, and then mounting a semiconductor element, The internal wiring is performed, then the resin is sealed with transfer mold, and then the wiring board on which the semiconductor element is mounted is separated from the substrate frame to produce a low-priced, small, thin, fine-pitch semiconductor device. .

[0007]

A semiconductor device formed by the push-back method described above is formed on a main surface of the wiring substrate, and has a predetermined taper formed on a side surface formed by transfer molding for covering the semiconductor element. A resin sealing body having an angle is provided, and a side end of the resin sealing body in contact with the main surface of the wiring board is in contact with an end of each side of the wiring board. That is, in the pushback method, a wiring board is formed by pushback on a printed wiring board that is a material of a substrate frame, semiconductor elements are mounted in this area, internal wiring is performed, resin sealing is performed, and a semiconductor device is assembled. Perform processing. After performing this process, the wiring substrate is separated from the substrate frame to form a plurality of semiconductor devices on each of which a semiconductor element is mounted. The semiconductor device having the above structure is formed by such a conventional method.

However, when this push-back method is used, a whitening phenomenon may occur in which a solder resist film such as a photoresist formed on a wiring substrate becomes cloudy. That is, the solder resist required for the plating process for forming the connection electrodes and the like is applied and formed before the pushback process is performed. Therefore, the solder resist film is also cut during the push back. At this time, a whitening phenomenon occurs. It seems that the viscosity of the resist is related, but there is a problem that the solder resist film becomes brittle due to the whitening phenomenon. The present invention has been made under such circumstances, and in a semiconductor device in which a semiconductor element sealed with a resin is mounted on a wiring board,
Providing a semiconductor device having a miniaturized package;
In addition, the present invention provides a method of manufacturing a semiconductor device which is most easily automated and is most suitable for mass transfer, low cost and high reliability in a transfer molding process, and a push-back type substrate frame used in this method.

[0009]

According to the present invention, a side end of a resin sealing body which is in contact with a first surface of a wiring board on which a semiconductor device of a push-back type is formed is an end of each side of the wiring board. The solder resist film substantially in contact with or in close proximity to the portion, and formed in the periphery on the first surface of the wiring board and in the region near the periphery is formed of a thermosetting resist film; The solder resist film formed in a region other than the above is formed of a photoresist film. Further, according to the present invention, when a solder resist is applied to a push-back type substrate frame, a thermosetting resist film is formed at least in the vicinity of the push-back line on the first surface in the vicinity thereof, and is formed in other regions. Is characterized by forming a photoresist film. Further, the present invention is characterized in that a means is provided to oppose a wiring board formed on a push-back type substrate frame and to be close to a push-back line to reduce distortion at the time of push-back. At the time of pushback, the thermosetting resist film used for the solder resist even when the punch cuts the substrate frame by using the thermosetting resist formed in the peripheral area of the first surface of the wiring board that contacts the punch, Since the viscosity is higher than that of the photoresist, the whitening phenomenon is less likely to occur. By forming the strain relaxation means such as a slit, the push-back process is quickly performed.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. First, a semiconductor device having a wiring board will be described with reference to FIGS. FIG. 1 is a perspective view of a semiconductor device partially cut away to show the inside, and FIG.
FIG. 2 is a plan view and a bottom view of the semiconductor device as viewed from below. Wiring board 1 according to the present invention formed from board frame by pushback
Is, for example, a square of 11.00 × 11.00 mm, and the semiconductor element 2 is mounted on the first surface. The semiconductor element 2 is first bonded with an insulating adhesive such as an epoxy resin.
Is joined to the surface. Wiring (not shown) on the first side
And a plurality of connection electrodes (pads) 32 connected to the wiring.

On the first surface, the pads 32 are exposed, but the wiring and other areas are covered with a solder resist. Although a detailed configuration will be described later, a region on the first surface along the periphery of the wiring board 1 is formed of a thermosetting resist film, and a photoresist film is formed on other regions. That is, a region along the pushback line on the first surface is covered with the thermosetting resist film. Conversely, a region along the push line on the second surface, which is the back surface, may be covered with a thermosetting resist film. The second surface, which is the back surface of the wiring board 1, is also covered with a solder resist except for pads (not shown). The solder resist on the second surface is made of, for example, a photoresist film 29, and a solder bump terminal (solder ball) 5 is bonded to the pad. The pad formed on the second surface and the wiring formed on the main surface are connected to each other. The wiring on the first surface and the wiring on the second surface are connected to through-hole holes formed in the wiring board 1. They are electrically connected to each other via wiring formed on the inner surface. For example, 12 × 12 solder balls 5 are arranged and arranged. The pad 32 on the first surface and the pad 31 formed on the semiconductor element 2 are electrically connected by a bonding wire 4 such as Au or Al.
The semiconductor element 2, the bonding wires 4, the insulating adhesive 6, the pads on the first surface, and the like are covered with a resin sealing body 13 formed of epoxy resin or the like. The length of one side of the bottom surface of the resin sealing body 13 is 10.8 mm. The resin sealing body 13 is slightly smaller than the wiring board 1 but has substantially the same size. The length of the one side may completely match the wiring board 1. An index mark (circle) is provided on the surface of the resin sealing body 13. The side surface of the resin sealing body 13 is inclined to have a taper angle of about 10 to 30 degrees with respect to the vertical, for example.

Next, with reference to FIG. 3, a description will be given of the substrate forming process up to the outer shape processing of removing the outer frame from the double-sided copper-clad laminate and performing slit processing. FIG. 3 is a flowchart for explaining steps up to the formation of a printed wiring board (substrate frame) for a pushback system. A heat-resistant double-sided copper-clad laminate with a TG temperature of 175 degrees Celsius or higher, in which a substrate frame is made of a heat-resistant glass cloth as a base material, impregnated with BT resin, laminated with the base material, and pasted with copper foil on both sides. (For example, CCL-HL832 BT substrate manufactured by Mitsubishi Gas Chemical Company) is cut into an arbitrary size for use. (1) First, a punching process is performed on this double-sided copper-clad laminate to form through holes, positioning holes, and the like. In this step, a feed hole used for transport is formed as necessary. In this embodiment, the substrate frame is transported while being held by a holder. FIG. 4A is a schematic plan view of the laminated plate formed by this step. A predetermined wiring board area 33 is provided on the laminate, and the positioning holes 7 are provided.
And through holes (not shown). The substrate thickness of the laminate is optimally 0.2 to 0.4 mm. The drill used for drilling through-holes should be 0.1 to
Use the one with a diameter of 0.2 mm.

(2) Thereafter, the copper foil is patterned,
Further, through-hole plating (Cu film of about 10 μm)
To form a wiring pattern in which the wiring on both sides of the laminate is connected. FIG. 4B is a schematic plan view of the laminated board formed by this process. In the wiring board region 33, a wiring pattern (not shown) and a connection electrode 32 are regions where a semiconductor element is to be mounted. It is formed near the periphery of a certain island portion 9. (3) Thereafter, a solder resist is formed in a predetermined pattern on both sides of the laminate and in the through holes. FIG.
5A is a plan view of the surface of the laminate, and FIG. 5B is a plan view of the back of the laminate. The solder resist used at this time is a thermosetting resist film 2 having a relatively high viscosity on at least one of the front and back surfaces corresponding to the pushback processing surface.
8, for example, it was optimal to coat with a CCR232CFV (made by Asahi Kaken) and use a photoresist film 29 having excellent plate making properties on the other surface. The thermosetting resist film is formed by screen printing, and has high viscosity but poor workability, and its use must be reduced as much as possible. for that reason,
A thermosetting resist film is formed only in a narrow range on one of the front and back pushback lines of the pushback processing surface.

In another region, a photoresist film 29 is formed. The thermosetting resist film is formed, for example, from a black matte type paste two-part thermosetting solder resist using a special epoxy resin and a special curing agent. This thermosetting solder resist has a viscosity (25 ° C.) of 28
0ps, applicable screen for screen printing is 150 ~
Screen printing is performed under the conditions of 250 mesh, curing conditions of 130 ° C. for 10 minutes, and electrical insulation of 2.0 × 10 ¹² Ω. The photoresist film is formed from a development-type solder resist ink. This resist ink has, for example, a nonvolatile component of 70 to 80 wt% and a viscosity (25 ° C.) of 200%.
２２０220 ps, exposure amount is 400 to 800 mJ / cm ² ,
Developing time is 60 to 90 seconds, post-curing is performed by hot air circulation furnace for 60 minutes (150 ° C), and electrical insulation before processing is ≧ 1 ×
It is applied to the substrate frame under the condition of 10 ¹³ Ω. (4) Next, a plating process of a Cu layer and a Ni / Au layer is performed on the laminate, and the pad 32, as shown in FIG. 5A and FIG.
35 is formed.

(5) After that, external processing such as slit processing is performed to form a substrate frame. The slit 30
It is formed around the wiring board area 33 of the board frame 10 and is used as a means for alleviating distortion during pushback. Therefore, the outer shape processing is also a preliminary step of the pushback step. The slit processing is optimally about 0.5 to 0.8 mm as the support width and the slit processing width (slit length) is equal to or less than 0.3 mm as the pushback width (length of one side). there were. After the slit processing, the substrate is cut and separated into individual substrate frames 10. FIG. 6A is a plan view illustrating a surface state of the substrate frame 10, and FIG. 6B is a plan view illustrating a rear surface of the substrate frame 10. In this embodiment, the wiring board region 33 is a square having a side of 11.0 mm, and the slits 30 are arranged so as to face each side of the wiring board region 33 so that their length directions are parallel to each other. From this area 1.
0 mm apart. The slit length is 10.7m
m, which is 0.3 mm shorter than one side of the wiring board region 33. The slit width is 2.0 mm. next,
With reference to FIGS. 7, 8 to 13, steps from mounting a semiconductor element on the substrate frame 10 shown in FIG. 6 to performing pushback processing to manufacture a semiconductor device will be described.

FIG. 7 is a plan view of the substrate frame. The board frame 10 has positioning holes 7 on both sides thereof.
Are formed. In the central part of the substrate frame 10,
The wiring boards 1 are arranged at predetermined intervals. The wiring substrate 1 is formed by punching a substrate frame 10, and is pushed back again into an opening formed by the punching. The thickness of the substrate frame 10 is about 0.4
5 mm. At the boundary between the wiring board 1 and the board frame 10, a pushback line 8 is formed. In the wiring substrate 1, an island portion 9 which is a region where a semiconductor element is arranged is formed at a central portion, and a wiring pattern and a connection electrode 32 are formed slightly away from the island portion 9. A slit 30 is formed along each side of the wiring board so as to surround each wiring board 1. This is provided to alleviate distortion during pushback processing. In this embodiment, a temporary fixing portion is not provided in a part of the pushback line, but such a temporary fixing may be formed in the present invention. That is, the temporary fixing is performed as needed. The temporary fixing is formed by pressing or hitting the temporary fixing portion. The temporary fixing portion is preferably formed in a region (margin portion) where the wiring pattern is not formed, for example, near a corner of the wiring board. Due to this existence, the boundary regions approach each other, so that the force by which the board frame holds the wiring board can be improved. The temporary fixing part
It can be formed not only in one place but also in a plurality of places. The number is determined by the required holding force.

A resin sealing body is formed on the wiring board 1, and the processing is performed by an automatic machine to which a board frame on which the wiring board is mounted is transported. Next, FIGS.
1 will be described with reference to FIG. 8 and 9 are cross-sectional views of a manufacturing process of the semiconductor device, FIG. 10 is a cross-sectional view of a mold used in the manufacturing process, and FIG. 11 is a plan view illustrating an arrangement of a wiring substrate in a mold cavity. It is. First, FIG.
8 is prepared (FIG. 8A). The board frame 10 has a plurality of wiring board areas arranged at intervals. Connection electrodes and wiring patterns (not shown) are formed on the main surface of this region. Next, the outer shape punching is performed on the substrate frame 10, and the wiring substrate area is punched out by a die / punch to form a plurality of wiring substrates 1 (FIG. 8B). The punched wiring board 1 is pushed back to the board frame 10 with a predetermined force (F) (FIG. 8C). Thereafter, if necessary, a region such as a corner portion of the wiring board 1 on which the wiring pattern along the pushback line 8 is not formed is pressed to form a temporary fixing portion. is there). Next, the semiconductor element 2 is placed on the island portion of the wiring board 1 and fixed with an insulating adhesive or the like. The connection electrodes (not shown) exposed on the surface of the semiconductor element 2 and the connection electrodes (not shown) on the main surface of the wiring board 1 are electrically connected by bonding wires 4 such as gold wires (FIG. 9 ( a)).

Next, after arranging and fixing the substrate frame 10 in a mold, a liquefied mold resin is filled into the cavity by transfer molding and cured to form a resin sealing body 13 (FIG. 9 ( b)). Next, a bump electrode (solder ball) 5 such as solder, which is electrically connected to the connection electrode and electrically connected to an external circuit, is formed on the back surface of the wiring board 1. The connection electrodes on the main surface of the wiring board 1 and the solder balls 5 attached to the back surface are
Are electrically connected via connection electrodes (not shown) formed on the inner surfaces of the through holes (not shown) formed in the above.
This solder ball 5 is connected to a wiring pattern of a circuit board (not shown) to which another wiring board is attached (FIG. 9).
(C)). Thus, the semiconductor device is completed in a state where the wiring substrate is held by the substrate frame. The solder balls 5
The wiring board 1 may be detached from the board frame 10 and then attached. Depending on the specifications, the solder ball may be printed by soldering or the plating electrode may be used as it is. Thereafter, after stamping the company name, product name, and serial number, the product is removed from the substrate frame 10 (at this time, it is easily removed because of push-back processing), thereby completing the product of the present invention.

Next, a mold used in the transfer molding step will be described with reference to FIGS. The mold cavity 18 is formed by the lower mold cavity block 14 and the upper mold cavity block 15. The substrate frame 10 holding the wiring substrate 1 is provided in the cavity 18.
Is mounted and fixed. The lower and upper mold cavity blocks are fixed by a lower mold cavity holder 16 and an upper mold cavity block 17. The semiconductor element 2 and the bonding wires 4 are mounted on the wiring board 1 in the cavity 18. The bonding wire 4 electrically connects a connection electrode (not shown) of the semiconductor element 2 and a connection electrode 32 formed on the main surface of the wiring board 1. The substrate frame 10 is fixed so that the peripheral portion of the concave portion forming the cavity 18 of the upper mold cavity block 15 rides on the pushback line 8. In FIG. 11, the pushback line 8 should match the dotted line indicating the area of the cavity 18, but the line of the cavity 18 is displayed somewhat smaller in order to clarify the positional relationship. Mold resin made of epoxy resin etc.
The resin sealing body is formed by press-fitting the runner 27 and the gate 19 into the cavity 18.

Next, a semiconductor device in which a semiconductor element is flip-chip connected to a wiring board will be described with reference to FIG.
The figure is a cross-sectional view of the semiconductor device. The wiring board 1 is shown in FIG.
Formed from the substrate frame. The wiring board 1 has a through hole 25 formed therein. A connection electrode 26 made of a nickel plating film or the like is formed around the through hole 25 on the main surface and the back surface of the wiring substrate 1 and on the inner surface of the through hole. The rear surface of the wiring board 1 is electrically connected to the connection electrode 26 and electrically connected to an external circuit.
A solder ball 5 having a diameter of about 0.4 mm is formed.
On the other hand, a solder ball 24 having a diameter of about 80 μm is mounted on the connection electrode (not shown) also on the main surface of the semiconductor element 2. The solder balls 5 are connected to a wiring pattern of a circuit board (not shown) to which another wiring board is attached. The connection electrode 26 also extends to the main surface side of the semiconductor element 2 and is connected to the solder ball 24 of the semiconductor element 2. The semiconductor element 2 is covered with a resin sealing body 13 such as an epoxy resin formed by transfer molding. Since the resin sealing body 13 is formed by a mold by transfer molding, its side surface is tapered. For example, the taper angle is 10 to 30 with respect to the vertical direction.
Degrees.

Each side of the bottom surface of the resin sealing body 13 is arranged along each side of the wiring board 1. That is, the wiring board 1
And the bottom surface of the resin sealing body 13 have substantially the same shape and the same size. If the bottom surface of the resin sealing body slightly exceeds the main surface of the wiring board, the resin sealing body is likely to be damaged, such as being chipped, so that even if the bottom surface retreats from the main surface, do not exceed it. Is important. Next, FIG.
A semiconductor device in which external connection electrodes are formed on side surfaces of a wiring board will be described with reference to FIG. FIG. 1 is a plan view of a semiconductor device and a cross-sectional view of a portion thereof along line AA ′. Wiring board 1
Are formed from a push-back type substrate frame. An external connection electrode 3 made of a nickel plating film or the like is formed on the wiring board 1 along the pushback line 8. The connection electrode 32 is formed on the first surface of the wiring board 1 and is electrically connected to a wiring pattern 34 formed integrally with the connection electrode. The semiconductor element 2 is formed in the center of the wiring substrate 1, and the connection pattern (pad) of the semiconductor element 2 and the wiring pattern 34 on the wiring substrate 1 are formed.
And the connection electrode 32 formed integrally therewith is electrically connected by a bonding wire 4. The end of the bottom surface of the resin sealing body 13 that contacts the wiring board 1 is formed along the side of the wiring board 1. That is, each side of the bottom surface of the resin sealing body matches or is close to each side of the wiring board.

Further, in the present invention, since a push-back type substrate frame is used, it is possible to collect only non-defective products or to collect the same-quality wiring substrates in one substrate frame for transporting the wiring substrate in the process of assembling the semiconductor device. it can. Therefore, the assembling process becomes more efficient.
Next, the solder resist formed on the substrate frame will be described with reference to FIG. FIG. 14 is a partial cross-sectional view of the portion A (FIG. 7) of the substrate frame, showing a state where the semiconductor element is mounted on the substrate frame. The left side of the push-back line 8 of the board frame 10 shown in FIG. First and second surfaces of wiring substrate 1 and through hole 25 formed in hole forming step (1)
Inside, a wiring pattern 34 and a plating film 36 are formed, respectively. The wiring pattern 34 and the through-hole plating film 36 are covered with a solder resist.
Conventionally, only a photoresist having good plate making properties has been used as the solder resist. Pushback processing is performed by die /
Although it is economical to perform by pressing with a punch, if the solder resist on the substrate frame at the cut surface is hard, cracks are likely to occur, so in the present invention, at least one of the front and back pushback processed surfaces is made of the above-mentioned viscous High thermosetting resist film.

Therefore, in this embodiment, the thermosetting resist film 2 is formed on the portion of the first surface including the push-back line 8.
8 is formed, and a photoresist film 29 is formed in other regions. As shown in FIG. 8, the portion where the thermosetting resist film 28 is formed is a place where the punch is abutted and cut first, so that a highly viscous material such as a thermosetting resist film is used. . The pad 32 on the first surface and the pad 35 formed on the second surface and joined to the solder ball 5 are:
Electrical connection is made via a plated film 36 formed in the through hole 25 of the wiring board 1. The pad 35 is electrically connected to a pad (not shown) of the semiconductor element 2 by a bonding wire 4. The semiconductor element 2 is joined to the wiring board 1 by the insulating adhesive 6. The semiconductor element 2, the bonding wires 4, the pads 32, and the like are sealed in a resin sealing body 13 such as an epoxy resin.

The present invention provides a highly reliable encapsulation method by providing a semiconductor device with a substrate of the same material as the mounting substrate on which the semiconductor device is mounted, and by performing push-back processing in advance during the fabrication of the device substrate. It is to provide a so-called CSP that can be taken out with almost the same dimensions as the transfer mold even though it is a transfer mold. According to the conventional method, when an attempt is made to provide a semiconductor device using the same material as that of the mounting substrate, at least 0.7 mm on one side in consideration of plate thickness + transfer mold position accuracy + press cutting accuracy from transfer mold dimensions. ~ 1.0mm
Only a so-called flange type semiconductor having a margin can be provided. There is also a method of cutting them at the final stage with a router or a laser, but not only does the cost of the CSP increase, but it cannot be reduced to the push-back method.
The most important point of the present invention is to consider the waste of resources and resources, to devise conventional technologies, materials, and methods, and to use inexpensively and simply small and thin CS using conventional withered processes and equipment.
P. This can be solved by making the slit shape approximately the same as the size allowed for the product, performing pushback processing, and performing transfer molding.

Since such a CSP according to the present invention is equivalent to a substrate to be mounted, the reliability has been significantly improved without receiving any thermal shock. Also, there is no particular cost or development cost, and the conventional equipment can be used as it is in the manufacturing process, and a small and thin CSP that is technically stable and inexpensive can be provided. In the above description, the CPS using the heat-resistant copper-clad laminate has been described, but the present invention can be achieved with a substrate made of another organic material. Also, the present invention
As described in the ball grit array, the effect may be applied to an LGA (lead grit array) without any change.
In this case, reinforcing pads can be provided on the surrounding four corners to further enhance the reliability of mounting.

[0026]

According to the push-back type semiconductor device of the present invention, which is resin-sealed on the wiring board, the size of the push-back type substrate can be sufficiently reduced without deterioration of the solder resist at the time of push-back. Since the assembly process is performed using the frame, automation can be efficiently performed. Further, the push-back can be quickly performed by the strain relief means formed on the substrate frame, and the capability of holding the wiring substrate of the push-back type substrate frame can be greatly improved by the temporary fixing portion. .

[Brief description of the drawings]

FIG. 1 is a perspective view of a semiconductor device of the present invention and a cross-sectional view of a portion taken along line AA ′.

FIG. 2 is a plan view and a bottom view of the semiconductor device of FIG.

FIG. 3 is a manufacturing process diagram showing the steps up to manufacturing the substrate frame of the present invention.

FIG. 4 is a plan view of the substrate frame of the present invention.

FIG. 5 is a plan view of the substrate frame of the present invention.

FIG. 6 is a plan view of the substrate frame of the present invention.

FIG. 7 is a plan view and a cross-sectional view of the substrate frame of the present invention.

FIG. 8 is a manufacturing process cross-sectional view illustrating the manufacture of the semiconductor device of the present invention.

FIG. 9 is a manufacturing process cross-sectional view illustrating the manufacture of the semiconductor device of the present invention.

FIG. 10 is a sectional view of a mold used for manufacturing a semiconductor device of the present invention.

FIG. 11 is a plan view of a cavity portion of the mold of FIG. 10;

FIG. 12 is a cross-sectional view of a semiconductor device of the present invention.

FIG. 13 is a plan view of a semiconductor device according to the present invention and a cross-sectional view taken along a line AA ′.

FIG. 14 is a partial cross-sectional view of the substrate frame showing a portion A in FIG. 7;

FIG. 15 is a cross-sectional view of a conventional semiconductor device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Wiring board 2 ... Semiconductor element 3 ...
..External connection electrodes, 4, bonding wires, 5,
24: solder bump terminal (solder ball), 6:
Insulating adhesive, 7: positioning hole, 8: push-back line, 9: island, 10.
..Substrate frames, 13 and 20.
14 ... lower mold cavity block, 15 ... upper mold cavity block, 16 ... lower mold cavity holder, 17 ... upper mold cavity holder, 18 ...
・ Cavity, 19 ・ ・ ・ Gate, 25 ・ ・ ・ Through hole, 26 ・ ・ ・ Connection electrode, 27 ・ ・ ・ Runner, 28 ・ ・ ・ Thermosetting resist film, 29 ・ ・ ・ Photoresist film, 30 ・ ・・ Slit, 31 ...
Pads on the chip, 32, 35: Connection electrodes (pads), 33: Wiring board area, 34: Wiring pattern, 36: Through-hole plating film.

Claims (10)

[Claims] 1. A first and a second wiring pattern, wherein a plurality of connection electrodes electrically connected to the wiring pattern are formed, and a resist film is formed in a region other than a region where the connection electrode is formed. A semiconductor device mounted on a first surface of the wiring substrate and electrically connected to the wiring pattern; and a semiconductor device formed on the first surface of the wiring substrate and A resin mold having a predetermined taper angle on a side surface formed by transfer mold for covering the wiring board, and a side end of the resin mold in contact with the first surface of the wiring board is provided on each side of the wiring board. The resist film substantially in contact with or close to the edge of the side, and formed in the periphery on the first surface of the wiring substrate and in the region near the periphery,
A semiconductor device comprising a thermosetting resist film, wherein the resist film formed in a region other than the region is composed of a photoresist. 2. The semiconductor device according to claim 1, wherein the wiring board is formed by separating a plurality of wiring board formation regions from a substrate frame to which the push-back is performed. 3. A step of preparing a substrate frame on which a plurality of wiring substrate forming regions on which wiring patterns are provided are formed; a step of forming a resist film in a predetermined region of the substrate frame; Forming a plurality of connection electrodes electrically connected to the wiring pattern in a region other than the predetermined region where the film is formed; punching the substrate frame along the wiring substrate formation region; A step of pushing back a wiring board to an original position of the board frame; a step of mounting a semiconductor element on a first surface of the wiring board; and a step of electrically connecting the semiconductor element and the wiring pattern Transfer molding a resin sealing body covering the first surface of the wiring substrate and the semiconductor element thereon and having a predetermined taper angle on the side surface thereof. Forming the wiring substrate from the substrate frame, and removing the wiring substrate from the substrate frame, wherein a side end of the resin sealing body in contact with a first surface of the wiring substrate is an end of each side of the wiring substrate. The resist film substantially in contact with or in close proximity to the portion, and formed along the inside and outside of this region around the boundary on the first surface side of the wiring board formation region formed in the substrate frame, A method of manufacturing a semiconductor device, comprising: a thermosetting resist film; and the resist film formed in other regions is formed of a photoresist film. 4. A step of forming solder bumps on the second surface of the wiring board via the connection electrodes before or after the step of removing the wiring board from the substrate frame after forming the resin sealing body. The method for manufacturing a semiconductor device according to claim 3, further comprising: 5. The wiring on a boundary region between the substrate frame and the wiring board before mounting and fixing the semiconductor element following the step of pushing back the wiring board to an original position of the substrate frame. 5. The method of manufacturing a semiconductor device according to claim 3, wherein a temporary fixing portion for enhancing holding of the wiring substrate is formed in a predetermined region in a region where the pattern is not formed. 6. In the step of forming the resin sealing body by transfer molding, the transfer molding is performed in a mold, and the substrate frame has a cavity side arranged along a side of the wiring board. 6. The method of manufacturing a semiconductor device according to claim 3, wherein the semiconductor device is mounted on the mold so as to be mounted on the mold. 7. An insulating substrate having a plurality of punched-out openings, a resist film pushed back into the openings and formed in a predetermined region other than the predetermined region in which the resist film, the wiring pattern and the resist film are formed. A plurality of wiring boards in which a plurality of connection electrodes electrically connected to the wiring pattern are formed in a region, and a center of the wiring board formed on the substrate frame on a first surface side boundary The substrate, wherein the resist film formed along the inside and outside of the region is formed of a thermosetting resist film, and the resist film formed in other regions is formed of a photoresist film. flame. 8. A temporary fixing portion for strengthening the holding of the wiring substrate is provided in a predetermined region in a region where the wiring pattern is not formed on a boundary region between the insulating substrate and the wiring substrate in the opening. The substrate frame according to claim 7, wherein the substrate frame is formed. 9. The board frame according to claim 7, wherein means is provided near the periphery of the wiring board to reduce distortion during pushback. 10. The board frame according to claim 9, wherein said strain reducing means is a slit provided on each side of said wiring board.