JPH07312376A - Method of manufacturing resin sealing type semiconductor device - Google Patents

Abstract

PURPOSE:To enhance manufacturing yield in an assembling process by a method where the sealing part of a tab and a tab suspending lead, a sealing part of a lead, a semiconductor pellet and a bonding wire are arranged within the cavity of a molding die, and then resin is filled. CONSTITUTION:When a region arranging each of tape dams 3D of a tab suspending lead 3B and a lead 3C is interposed between an upper die 6A and a lower die 6B of a molding die 6, it is possible to prevent the location slippage of the tab 3A caused by the bend of the tab suspending lead 3B due to the elastic force of the tape dam 3D by using a support member 5. Accordingly, it is possible to prevent the generation of the difference in speeds between the flowing speed of resin 1A flowing on a main surface of a semiconductor pellet 2 and a flowing speed of resin 1A flowing on the rear surface of the tab 3A. As a result, as it is possible to prevent a short-circuit between bonding wires due to wire flowing or the generation of voids due to enfolding of bubbles, it is possible to increase manufacturing yield in an assembling process of a resin sealing type semiconductor device.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a resin-sealed semiconductor device, and more particularly to a technique effectively applied to a method of manufacturing a resin-sealed semiconductor device using a tape dam type lead frame. Is.

[0002]

2. Description of the Related Art As a resin-sealed semiconductor device, for example, Q
FP (Q uad F lat P ackage ) resin-sealed semiconductor device which employs the structure is. This type of resin-sealed semiconductor device
The semiconductor pellets are mounted on the pellet tower mounting surface of the tab in which the tab suspension leads are integrated.

The resin-sealed semiconductor device adopting the QFP structure uses a tape dam type lead frame in its assembly process. A resin-sealed semiconductor device using this tape dam type lead frame is generally formed by the following assembly process.

First, a tape dam type lead frame is prepared. In this tape dam type lead frame, a tab supported by interposing a tab suspension lead on the frame body and a lead supported by the frame body are arranged in an area defined by a frame body, A tape dam is arranged on the region between the sealing part and the non-sealing part of the suspension lead, and on the region between the sealing part (inner lead) and the non-sealing part (outer lead) of the lead. . The tape dam is formed in a ring shape along the outer peripheral shape of the tab, and connects between the leads and between the lead and the tab suspension lead.

Next, semiconductor pellets are mounted on the pellet mounting surface of the tab of the lead frame (die bonding).
To do.

Next, the lead sealing side of the lead frame and the external terminal (bonding pad) of the semiconductor pellet are electrically connected by a bonding wire.

Next, the lead frame is placed between an upper die and a lower die of a molding die, and a sealing portion for the tab and the tab suspension lead is provided in a cavity formed by the upper die and the lower die. ,
After the lead sealing portion, the semiconductor pellet, the bonding wire, and the like are arranged, the tab suspension lead and the tape dam arrangement region of the lead are sandwiched between the upper die and the lower die of the molding die.

Next, a resin is filled in the cavity of the molding die, and the resin is used to seal the tab, the tab suspension lead sealing portion, the lead sealing portion (inner lead), the semiconductor pellet, the bonding wire, and the like. Seal.

Next, from the frame of the lead frame, the tab suspension lead sealing portion and the lead non-sealing portion (outer leads)
After that, the non-sealing portion of the lead is formed into a predetermined shape (eg, gull wing shape). This allows
A resin-sealed semiconductor device using a tape dam type lead frame is almost completed.

[0010]

The present inventor has found the following problems with respect to the resin-sealed semiconductor device using the above-mentioned tape dam type lead frame.

In the process of assembling the resin-encapsulated semiconductor device, when the tape dam placement regions of the tab suspension lead and the lead are sandwiched between the upper mold and the lower mold of the molding die, the tab dam is elastically driven by the elastic force of the tape dam. Warping occurs in the suspension leads, and it is perpendicular to the main surface of the semiconductor pellet (vertical direction).
The tab position is shifted to. The displacement of the tab causes a velocity difference between the flow velocity of the resin flowing on the main surface of the semiconductor pellet and the flow velocity of the resin flowing on the back surface of the tab when the resin is filled in the cavity of the molding die. For this reason, there is a problem that a short circuit between bonding wires due to wire flow, a void due to entrainment of air bubbles, and the like occur, and the yield in the assembly process of the resin-sealed semiconductor device decreases.

An object of the present invention is to provide a technique capable of increasing the yield in the assembly process of resin-sealed semiconductor devices.

The above and other objects and novel features of the present invention will be apparent from the description of this specification and the accompanying drawings.

[0014]

Among the inventions disclosed in the present application, a brief description will be given to the outline of typical ones.
It is as follows.

In a method of manufacturing a resin-encapsulated semiconductor device using a tape dam type lead frame, (a) a tab suspension lead is supported by the frame body within a region defined by the frame body. A tab and a lead supported by the frame are arranged, and between the sealed portion and the non-sealed portion of the lead on the region between the sealed portion and the non-sealed portion of the tab suspension lead. A step of preparing a lead frame in which a tape dam is arranged in each of the areas; (b) a step of mounting semiconductor pellets on a pellet mounting surface of the tab of the lead frame; and (c) a main portion of the semiconductor pellets. Fixing a supporting member on each of the surfaces of the tub, which faces the pellet mounting surface of the tub, and (d) electrically connects the leads of the lead frame and the external terminals of the semiconductor pellets with bonding wires. (E) Placing the lead frame between the upper die and the lower die of the molding die, and suspending the tab and the tab in the cavity formed by the upper die and the lower die of the molding die. A step of arranging the lead sealing portion, the lead sealing portion, the semiconductor pellet and the bonding wire,
(F) The tab suspension lead and the region where each tape dam of the lead is arranged are sandwiched by the upper die and the lower die of the molding die, and the main surface of the semiconductor pellet is sandwiched by a supporting member to form the semiconductor. Supporting the inner wall surface of the cavity facing the main surface of the pellet, and supporting the back surface of the tab on the inner wall surface of the cavity facing the back surface of the tab through a supporting member; and (g) the molding die. Filling the inside of the cavity with a resin, and sealing the tab, the tab suspension lead sealing portion, the lead sealing portion, the semiconductor pellet, and the bonding wire.

[0016]

According to the above-mentioned means, when the tape dam placement regions of the tab suspension lead and the lead are sandwiched between the upper mold and the lower mold of the molding die, the tab suspension lead warps due to the elastic force of the tape dam. Since the supporting member can prevent the tab from being displaced, a difference in speed between the flow rate of the resin flowing on the main surface of the semiconductor pellet and the flow rate of the resin flowing on the back surface of the tab can be prevented. As a result, it is possible to prevent a short circuit between the bonding wires due to the wire flow and the occurrence of voids due to the inclusion of air bubbles, so that the yield in the assembly process of the resin-sealed semiconductor device can be increased.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The structure of the present invention will be described below together with an embodiment in which the present invention is applied to a resin-sealed semiconductor device using a tape dam type lead frame. In all the drawings for explaining the embodiments, parts having the same function are designated by the same reference numerals, and repeated description thereof will be omitted.

FIG. 1 is a schematic view of a resin-encapsulated semiconductor device using a tape dam type lead frame according to an embodiment of the present invention (a plan view of the resin encapsulant with an upper portion removed).
2 and FIG. 2 (a cross-sectional view taken along the line AA shown in FIG. 1).

As shown in FIGS. 1 and 2, the resin-sealed semiconductor device has a QFP type package structure. The resin-encapsulated semiconductor device has, for example, the semiconductor pellet 2 on the pellet-mounting surface of the tab 3A having a rectangular planar shape.
To install.

The semiconductor pellet 2 is composed mainly of, for example, a single crystal silicon substrate having a rectangular plane.
On the main surface of the semiconductor pellet 2, a plurality of external terminals BP are arranged in the outermost peripheral portion along each side of the rectangular shape.

The external terminal BP of the semiconductor pellet 2 is electrically connected to the sealing portion (inner lead) 3C1 side of the lead 3C via a bonding wire 4. A plurality of sealing portions 3C1 of the lead 3C are arranged along each side of the tab 3A. The sealing portion 3B1 of the tab suspension lead 3B is integrated with each of the four corners of the tab 3C.

The tab 3A, the sealing portion 3B1 of the tab suspension lead 3B, the sealing portion 3C1 of the lead 3C, the semiconductor pellet 2, the bonding wire 4, etc. are sealed with a resin sealing body 1. The resin encapsulant 1 is formed of, for example, an epoxy resin 1A to which a phenol-based curing agent, silicone rubber, and a filler are added in order to reduce stress, and is molded based on a transfer molding method.

A support member 5 is fixed to each of the main surface of the semiconductor pellet 2 and the back surface of the tub 3A facing the pellet mounting surface of the tub 3A. The support member 5 is formed of an epoxy resin, for example, as in the resin sealing body 1 described above.

The resin encapsulant 1 is formed, for example, in a rectangular planar shape. A plurality of non-sealing portions (outer leads) 3C1 of the leads 3C are arranged along each side of the rectangular shape on the outer side of the outermost periphery of the resin sealing body 1. Further, ring-shaped tape dams 3D arranged along the respective sides of the rectangular shape are arranged on the outermost periphery of the resin sealing body 1.

Next, the assembly process of the resin-encapsulated semiconductor device will be briefly described with reference to FIG. 3 (a plan view for explaining the assembly process) and FIG. 4 (a cross-sectional view of an essential part for explaining the assembly process). To do.

First, as shown in FIG. 3, a tape dam type lead frame 3 is prepared. This lead frame 3
Is within the area defined by the frame 3E.
The tab 3 supported by E via the tab suspension lead 3B
A, each of the leads 3C supported by the frame 3E is arranged, and on the region between the sealing portion 3B1 and the non-sealing portion 3B2 of the tab suspension lead 3B, the sealing portion 3C1 of the lead 3C.
The tape dam 3 on the area between the non-sealing portion 3C2 and the non-sealing portion 3C2.
Place D. The tape dam 3D is formed in a ring shape along the outermost peripheral shape of the tab 3A, and connects between the leads 3C and between the lead 3C and the tab suspension lead 3A.

Next, the semiconductor pellets 2 are mounted on the pellet mounting surface of the tab 3A of the lead frame 3 (die bonding).

Next, the supporting member 5 is adhered and fixed to the main surface of the semiconductor pellet 2 and the back surface of the tab 3A, respectively.

Next, the lead 3C of the inner lead 3
And the external terminal B of the semiconductor pellet 2 on the side of the sealing portion 3C1.
It is electrically connected to P by a bonding wire 4.

Next, the lead frame 3 is molded into a molding die 6.
The mold 6 is placed between the upper mold 6A and the lower mold 6B.
The tab 3A, the sealing portion 3B1 of the tab suspension lead 3B, the sealing portion 3C1 of the lead 3C, the semiconductor pellet 2, the bonding wire 4, and the like are arranged in the cavity 7 formed by the upper mold 6A and the lower mold 6B.

Next, as shown in FIG. 4, the regions in which the tape dams 4D of the tab suspension leads 3B and leads 3C are arranged are sandwiched between the upper die 6A and the lower die 6B of the molding die 6. Along with (clamping), the main surface of the semiconductor pellet 2 is supported by the inner wall surface of the cavity 7 facing the main surface of the semiconductor pellet 2 via the support member 5, and the back surface of the tab 3C is supported by the support member 5. It is supported on the inner wall surface of the cavity 7 opposed to the back surface of the tab 3C via. At this time, the tab suspension lead 3B due to the elastic force of the tape dam 3D
The support member 5 can prevent the tab 3A from being displaced due to the warp. The height (length) of the supporting member 5 fixed on the main surface of the semiconductor pellet 2 is almost equal to the distance between the main surface of the semiconductor pellet 2 and the inner wall surface of the cavity 7 facing the main surface. Form. Further, the height of the support member 5 fixed on the back surface of the tab 3A is formed to be substantially equal to the distance between the back surface of the tab 3A and the inner wall surface of the cavity 7 facing the back surface.

Next, resin 1A is filled in the cavity 7 of the molding die 6, and the resin 1A is used to seal the tab 3A, the tab suspension lead 3B, the sealing portion 3B1, and the lead 3C.
The resin encapsulant 1 is molded by encapsulating C1, the semiconductor pellet 2, the bonding wire 4, and the like. At this time, since the displacement of the tab 3A is prevented by the support member 5, there is a speed difference between the flow rate of the resin 1A flowing on the main surface of the semiconductor pellet 2 and the flow rate of the resin 1A flowing on the back surface of the tab 3A. Can be prevented.

Next, the stopper 3B1 of the tab suspension lead 3B and the non-sealing portion (outer lead) 3C2 of the lead 3C are cut from the frame 3D of the lead frame 3, and then the non-sealing of the lead 3C is performed. The portion 3C2 is formed into a predetermined shape (gull wing shape). As a result, the resin-sealed semiconductor device using the tape dam type lead frame is almost completed.

Thus, in the process of assembling the resin-sealed semiconductor device using the tape dam type lead frame, the tab suspension leads 3B are interposed in the frame 3E within the region defined by the frame 3E. The tab 3A supported by the frame 3E and the lead 3C supported by the frame 3E are arranged, and the lead 3C is sealed on the region between the sealing portion 3B1 and the non-sealing portion 3B2 of the tab suspension lead 3B. Stop part (inner lead) 3C1 and non-sealing part (outer lead) 3C2
A lead frame 3 in which a tape dam 3D is arranged in each of the regions between and, a step of mounting the semiconductor pellets 2 on the pellet mounting surface of the tab 3A of the lead frame 3, and the semiconductor Fixing the support member 5 to each of the main surface of the pellet 2 and the back surface of the tab 3A facing the pellet mounting surface of the tab 3A;
Side of the sealing portion 3C1 of the lead 3C and the semiconductor pellet 2
Of electrically connecting the external terminal BP with the bonding wire 4 and the lead frame 3 is disposed between the upper die 6A and the lower die 6B of the molding die 6, and the upper die of this molding die 6 is disposed. Placing the tab 3A, the sealing portion 3B1 of the tab suspension lead 3B, the sealing portion 3C1 of the lead 3, the semiconductor pellet 2 and the bonding wire 4 in the cavity 7 formed by 6A and the lower mold 6B; Tab suspension lead 3B,
The area where each tape dam 3D of the lead 3C is arranged is sandwiched between the upper die 6A and the lower die 6B of the molding die 6, and the main surface of the semiconductor pellet 2 is sandwiched by the support member 5 to form the semiconductor pellet. 2 is supported on the inner wall surface of the cavity 7 opposed to the main surface of the tab 2, and the back surface of the tab 3A is supported by the support member
Supporting on the inner wall surface of the cavity 7 facing the back surface of the tab 3A through the resin, and filling the resin 1A into the cavity 7 of the molding die 6 to seal the tab 3A and the tab suspension lead 3B. 3B1, the sealing portion 3C1 of the lead 3C, the semiconductor pellet 2, and the bonding wire 4 are sealed. Thus, when the upper die 6A and the lower die 6B of the molding die 6 sandwich the area where the tape dam 3D of the tab suspension lead 3B and the lead 3C are arranged, the tab suspension lead 3B due to the elastic force of the tape dam 3D. Since the displacement of the tab 3A caused by the warp of the resin can be prevented by the support member 5, a speed difference occurs between the flow rate of the resin 1A flowing on the main surface of the semiconductor pellet 2 and the flow rate of the resin 1A flowing on the back surface of the tab 3A. Can be prevented. As a result, it is possible to prevent a short circuit between the bonding wires 4 due to the wire flow and the generation of voids due to the inclusion of air bubbles, so that the yield in the assembly process of the resin-sealed semiconductor device can be increased.

Instead of the support member 5 fixed to the back surface of the tab 3A, the heat radiation fins 8 may be directly fixed to the back surface of the tab 3A as shown in FIG. In this case, since the radiation fin 8 is directly fixed to the back surface of the tab 3A, the radiation efficiency of the resin-sealed semiconductor device can be improved.

As described above, the inventions made by the present inventor are
Although the specific description has been given based on the above-described embodiments, the present invention is not limited to the above-described embodiments, and it goes without saying that various modifications can be made without departing from the scope of the invention.

[0037]

The effects obtained by the typical ones of the inventions disclosed in the present application will be briefly described as follows.

The yield in the assembly process of the resin-sealed semiconductor device using the tape dam type lead frame can be improved.

[Brief description of drawings]

FIG. 1 is a plan view of a resin-sealed semiconductor device using a tape dam type lead frame according to an embodiment of the present invention with an upper portion of a resin-sealed body removed.

FIG. 2 is a cross-sectional view taken along the line AA shown in FIG.

FIG. 3 is a plan view of a lead frame for explaining an assembly process of the resin-sealed semiconductor device.

FIG. 4 is a sectional view of a main part of a molding die for explaining an assembly process of the resin-encapsulated semiconductor device.

FIG. 5 is a sectional view of a main part of a molding die for explaining an assembly process of a resin-sealed semiconductor device according to another embodiment of the present invention.

[Explanation of symbols]

1 ... Resin encapsulant, 1A ... Resin, 2 ... Semiconductor pellet, 3
... lead frame, 3A ... tab, 3B ... tab suspension lead, 3C ... lead, 3D ... tape dam, 3E ... frame body, 4
... Bonding wire, 5 ... Support member, 6 ... Mold,
7 ... Cavity.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Teruo Kitamura 2326 Imai, Ome City, Tokyo Metropolitan area, Hitachi Device Development Center (72) Inventor Hiroyuki Hozoji 2326 Imai, Ome city, Tokyo Hitachi Device Development Center Co., Ltd. (72) Inventor Kenji Sato, Nakajima 145, Nanae-cho, Kameda-gun, Hokkaido Inside Hitachi Hokkai Semiconductor Co., Ltd. (72) Inventor Fujiaki Nose 2326 Imai, Ome-shi, Tokyo Inside Hitachi Device Development Center (72) Invention Eiji Yamaguchi 2326 Imai, Ome-shi, Tokyo Within Hitachi Device Development Center (72) Inventor Yuji Watanabe 2326 Imai, Ome-shi, Tokyo Within Hitachi Device Development Center

Claims (1)

[Claims] 1. A method of manufacturing a resin-encapsulated semiconductor device, which comprises the following steps (a) to (g): (A) A tab supported by the frame body via a tab suspension lead and a lead supported by the frame body are arranged in a region defined by the frame body, and the tab suspension lead is sealed. Preparing a lead frame in which a tape dam is arranged on the region between the sealing portion and the non-sealing portion and on the region between the sealing portion and the non-sealing portion of the lead, respectively. A step of mounting semiconductor pellets on the pellet-column mounting surface of the tab of the frame; (c) fixing a supporting member on the main surface of the semiconductor pellet and on the back surface thereof facing the pellet-column mounting surface of the tab, respectively. Step (d) electrically connecting the leads of the lead frame and the external terminals of the semiconductor pellet with a bonding wire, (e) arranging the lead frame between an upper die and a lower die of a molding die Then, the upper and lower molds of this mold In the tub in a cavity formed, the sealing portion of the tab suspension leads, placing the sealing portion of the lead, the semiconductor pellet and the bonding wires,
(F) The tab suspension lead and the region where each tape dam of the lead is arranged are sandwiched by the upper die and the lower die of the molding die, and the main surface of the semiconductor pellet is sandwiched by a supporting member to form the semiconductor. Supporting the inner wall surface of the cavity facing the main surface of the pellet, and supporting the back surface of the tab on the inner wall surface of the cavity facing the back surface of the tab through a supporting member, (g) of the molding die A step of filling a resin into the cavity and sealing the tab, the tab suspension lead sealing portion, the lead sealing portion, the semiconductor pellet, and the bonding wire.