JPH10125828A - Semiconductor device and manufacturing thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent tabs from playing at forming of a resin seal. SOLUTION: Positioning protrusions for positioning tabs 16 are formed at the ceiling and bottom faces of the cavity of a mold for forming a resin seal 25. After forming the resin seal 25 having positioning protrusion marks 26a, 26b formed by the positioning protrusions are filled up with a charged resin 28. At forming the resin seal 25, the tabs 16 are positioned by the protrusions and hence never play due to the resin injected in the cavity. This prevents the tabs 16 from dislocating with their play, wires from exposing at the resin seal or from short-circuitting with the pellet, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technology for manufacturing a semiconductor device, and more particularly to a technology for preventing a tab from floating during molding of a resin sealing body. For example, the present invention relates to a semiconductor device having a surface mount type resin sealing package. The present invention relates to a technology effective for use in an integrated circuit device (hereinafter, referred to as an IC).

[0002]

2. Description of the Related Art An IC provided with a surface-mount type resin-sealed package includes a semiconductor pellet (hereinafter, referred to as a pellet), a tab to which the pellet is bonded, and
A plurality of inner leads electrically connected to each bonding pad of the pellet via a bonding wire, outer leads respectively connected to each inner lead, and a resin for sealing the pellet, tab and each inner lead. And a sealing body. In general, if the ratio of the resin thickness above the pellet to the resin thickness below the tab (hereinafter referred to as the up-down ratio) of the resin sealing body approaches “1”, the resin sealing body does not warp. When the distance from “1” is increased, the resin sealing body is warped. Therefore, conventionally, a so-called tab lowering is performed to make the vertical ratio of the resin thickness close to “1”.

[0003] As an example in which a resin-sealed package is described, see “VLSI Packaging Technology (above)” published on May 31, 1993 by Nikkei BP, Inc.
There are 164.

[0004]

In the above-described surface-mount type resin-sealed package, when the entire thickness of the resin-sealed body becomes thin, the tab becomes large, or the inner leads become dense. The tab is moved by the flow of a liquid resin (hereinafter, referred to as a resin) as a molding material during molding of the resin sealing body, displacement of the tab occurs, a wire is exposed from the resin sealing body, The wire may touch the pellet and cause a short circuit failure.

An object of the present invention is to provide a semiconductor device manufacturing technique capable of preventing a tab from floating during molding of a resin sealing body.

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

[0007]

The outline of a typical invention among the inventions disclosed in the present application is as follows.

In other words, at least one main surface of the inner surface of the cavity of the molding die for molding the resin sealing body is provided with a projection for regulating the position of the tab. A resin is filled into the position control protrusion mark formed by the control protrusion, and the position control protrusion mark is back-filled with the filled resin portion.

According to the above-described means, the position of the tab is regulated by the position regulating projection when molding the resin sealing body, so that the tab is prevented from floating due to the molding material injected into the cavity. Therefore, it is possible to prevent the displacement of the tab caused by the movement of the tab, the exposure of the wire from the resin sealing body, the short-circuit failure of the wire with the pellet, and the like.

[0010]

FIG. 1 is a partially cutaway perspective view showing a semiconductor device according to an embodiment of the present invention. FIG. 2 et seq. Are explanatory views showing respective steps in the manufacturing method.

In the present embodiment, the semiconductor device according to the present invention is provided with a surface-mount type resin-sealed package.
C is an example of a resin-sealed TSOP IC (Thin
Small Outline Package IC.
Hereinafter, it is called TSOP IC. ). The TSOP IC 29 includes a pellet 22, a tab 16 to which the pellet 22 is bonded, and a pellet 2.
2, a plurality of inner leads 18 electrically connected to the respective bonding pads 22a via bonding wires 23, outer leads 19 respectively connected to the respective inner leads 18, pellets 22, tabs 16, and respective inner leads 18. And a resin sealing body 25 for sealing the leads 18 with resin.

The resin sealing body 25 is formed in a rectangular flat plate shape in a plan view. A pair of main surfaces (hereinafter referred to as an upper surface and a lower surface) facing each other are formed with the resin sealing body 25. At this time, the upper position restricting convex trace 26a and the lower position restricting convex trace 26b are formed by the position restricting convex that restricts the position of the tab 16, and the upper position restricting convex trace 26a and the lower position restricting convex are formed. Imprint 26b
Are filled back by the filled resin portions 28, 28.

Hereinafter, a TSOP according to an embodiment of the present invention will be described.
-A method for manufacturing an IC will be described. By this explanation, TSO
The details of the above-described configuration for the P-IC will be made clear together.

In the method of manufacturing the TSOP IC, the multiple lead frame 11 shown in FIG. 2 is used.
The multiple lead frame 11 is manufactured and prepared by a multiple lead frame forming process. Multiple lead frame 1
Reference numeral 1 denotes a thin plate made of a spring material having relatively large mechanical strength, such as an iron-nickel alloy or phosphor bronze, and is integrally formed by punching press work or etching work. The surface of the multiple lead frame 11 has silver (A
A plating film (not shown) using g) or the like is partially or entirely applied so that wire bonding described later is appropriately performed. In the multiple lead frame 11, a plurality of unit lead frames 12 are arranged in a row in the horizontal direction. However, for convenience, only one unit is shown.

The unit lead frame 12 has a positioning hole 13
a is provided with a pair of outer frames 13 in which the two outer frames 13 are provided. The two outer frames 13, 13 are arranged in parallel at a predetermined interval and extend in series. A pair of section frames 14 are disposed between the adjacent unit lead frames 12 and 12 in parallel with each other between the outer frames 13 and 13 to be integrally bridged, and a rectangle formed by these outer frames and the section frames is formed. A unit lead frame 12 is formed in a frame (frame).

In the unit lead frame 12, tab suspension leads 15 are disposed at the center of each of the outer frames 13 and 13 so as to protrude at right angles, and a square is provided between the tips of the tab suspension leads 15 and 15. Are integrally supported. Both tab suspension leads 15, 15
Are bent in the vicinity of the tab 16, and the tab 16 is lowered about the thickness of the pellet described later from the surface of the inner lead group described later by the bending of each tab suspension lead 15 (so-called tab lowering). Is.). A pair of dam members 17, 17 are provided between the outer frames 13, 13 in parallel on both sides of the tab suspension lead 15, and are respectively erected. A plurality of inner leads 18 are arranged on the inner end side of the dam member 17 at equal intervals in the longitudinal direction and are integrally protruded perpendicularly to the dam member 17. Are arranged so that the tip surrounds the tab 16. On the other hand, the same number of outer leads 19 as the inner leads 18 are provided on the outer edge of the dam member 17.
The inner lead 18 is disposed so as to face the inner lead 18, and is integrally formed with the inner lead 18 so as to protrude integrally therewith. The outer end of each outer lead 19 is connected to the section frame 14, respectively. The portion between the adjacent outer leads 19 in the dam member 17 substantially constitutes a dam 17a for damping the flow of the resin at the time of molding the resin sealing body described later.

The multiple lead frame 11 according to the above configuration prepared in the multiple lead frame forming step includes:
In the pellet bonding step and the wire bonding step, a pellet bonding operation is performed, followed by a wire bonding operation. These bonding operations are sequentially performed for each unit lead frame by feeding the multiple lead frames at a pitch in the horizontal direction.

First, a pellet 22 as a semiconductor integrated circuit structure in which an integrated circuit is formed in a so-called pre-process in a manufacturing process of a semiconductor device by a pellet bonding operation, as shown in FIG. It is arranged at a substantially central portion on the tab 16 of the unit lead frame 12, and is bonded by being mechanically fixed by a bonding layer 21 formed between the tab 16 and the pellet 22. As a means for forming the bonding layer 21, a bonding method using a gold-silicon eutectic layer, a soldering layer, a silver paste adhesive layer, or the like can be used.

Subsequently, as shown in FIG. 3, each bonding pad 22 of the pellet 22 bonded on the tab 16 is formed by a wire bonding operation.
A bonding wire 23 is bonded between the inner lead 18 and each inner lead 18 by using a wire bonding device (not shown) such as an ultrasonic thermocompression bonding wire bonding device. Get entangled. As a result, the integrated circuit formed in the pellet 22 is electrically drawn out to the outside via the bonding pad 22a, the bonding wire 23, the inner lead 18 and the outer lead 19.

As described above, the pellet and the wire
In the bonded assembly 24 shown in FIG. 3, a group of resin sealing bodies 25 for performing resin sealing for each unit lead frame is provided with the transfer molding apparatus 3 shown in FIG.
0 is used to simultaneously mold the group of unit lead frames 12.

The transfer molding apparatus 30 shown in FIG. 4 includes a pair of upper mold 31 and lower mold 32 which are clamped to each other by a cylinder device or the like (not shown).
On the mating surface of the upper mold 31 and the lower mold 32, a plurality of sets of upper mold cavity recesses 33a and lower mold cavity recesses 33b are respectively provided so as to form the cavities 33 in cooperation with each other. In the present embodiment, the total height of the cavity 33 is 1 m so as to correspond to TSOP IC.
m or less.

The upper mold cavity recessed portion 33a and the lower mold cavity recessed portion 33b are each formed in a substantially rectangular hole shape when viewed from a plane. Upper cavity recess 33
A pair of upper position restricting convex portions 40a and lower position restricting convex portions 40b for restricting the position of the tabs are provided on the ceiling surface of a and the bottom surface of the lower mold cavity concave portion 33b so as to face each other. That is, both upper position regulating convex portions 40
a, 40a and both lower side position regulating projections 40b, 40b
Are arranged at respective positions facing the connection portion between the tab 16 and both tab suspension leads 15, 15. Is formed.

A pot 34 is opened on the mating surface of the upper die 31 and a cylinder device (not shown) is provided in the pot 34.
The plunger 35 which is moved forward and backward is inserted so that resin (hereinafter, referred to as resin) as a molding material can be fed. Cull 36 is pot 3 on the mating surface of lower mold 32
4 and a plurality of runners 37 are arranged radially so as to be connected to the cull 36, respectively. The other end of each runner 37 is connected to the lower cavity recess 33b, and a gate 38 is formed at the connection so that the resin can be injected into the cavity 33. Also, a rectangular shape slightly larger than the outer shape of the multiple lead frame 11 and a constant depth substantially equal to the thickness of the multiple lead frame 11 are provided on the mating surface of the lower mold 32 so that the escape recess 39 can escape the thickness of the lead frame. Has been submerged.

In the transfer molding, the assembly 24 having the above structure is accommodated in an escape recess 39 in which the multiple lead frames 11 are submerged in the lower mold 32, and the pellets 22 in each unit lead frame 12 are stored in each cavity. They are arranged and set to be accommodated in the tees 33, respectively. In this state, the two lower position regulating projections 40b, 40b in the lower mold cavity recess 23b are
The tabs 16 are respectively brought into contact with the respective connecting portions between the tab suspension leads 15, 15 and the tabs 16 from the lower side.
Is restricted from below.

Subsequently, the upper mold 31 and the lower mold 32 are clamped. In this state, the upper mold cavity concave portion 23a
The upper side position regulating projections 40a, 40a of the assembly 2
The tab 1 is brought into contact with each connection portion between the tab suspension leads 15 and 15 and the tab 16 from the upper side.
6 is restricted from above. Therefore, both sides of the tab 16 are sandwiched from above and below by the upper position regulating protrusions 40a, 40a and the lower position regulating protrusions 40b, 40b, and the position of the tab 16 is regulated in the cavity 23. State.

Thereafter, the resin 41 is fed from the pot 34 to the respective cavities 33 through the runner 37 and the gate 38 by the plunger 35 and injected. The resin 16 injected into the cavity 33 puts the tab 16 in a state in which the tab 16 is urged in the vertical direction. Since the tabs 16 are sandwiched from above and below by the portions 40b, 40b, the tab 16 does not move. Therefore, the displacement of the tab 16 caused by the movement of the tab 16, the exposure of the wire 23 from the resin sealing body 25, the short-circuit failure of the wire 23 with the pellet 22, and the like can be avoided.

After the injection, when the resin is thermally cured to form the resin sealing body 25, the upper mold 31 and the lower mold 32 are opened, and the resin sealing body is ejected by an ejector pin (not shown). 25 groups are released. Thus, FIG.
As shown in (2), the molded body 27 in which the resin sealing bodies 25 are molded is detached from the transfer molding apparatus 30. The tab 16, the pellet 22, the inner lead 18, and the wire 23 are in a resin-sealed state inside the resin-sealed body 25 formed as described above.

In this embodiment, the ceiling surface of the upper mold cavity recess 33a and the lower mold cavity recess 33b
A pair of truncated cone-shaped upper position regulating protrusions 40a and lower position regulating protrusions 40b are formed on the bottom surface of the resin sealing body 25 so as to face each other. Each upper position regulating protrusion mark (hereinafter referred to as an upper mark) 26a by each upper position regulating protrusion 40a and each lower position regulating protrusion mark (hereinafter referred to as a lower mark) by each lower position regulating protrusion 40b. ) 26b are formed in pairs. The upper traces 26a and the lower traces 26b are formed in frusto-conical holes, respectively, and are vertically opposed to each other with the tab suspension lead 15 interposed therebetween. Therefore, both tab suspension leads 15, 15 are provided with both upper marks 26a, 26a and both lower marks 26b, 26b.
Each hole is exposed at the bottom of the hole.

After that, as shown in FIG. 6, the upper traces 26a and the lower traces 26b are filled with a gel-like heat effect resin, and are buried by the filled resin portions 28, respectively. Since each tab suspension lead 15 is completely covered by each filling resin portion 28, the resin sealing body 25
Is totally closed.

Thereafter, a lead cutting and forming step (not shown)
In the above, the outer frame 13, the section frame 14, and the dam 17a are cut off for each unit lead frame, and the outer leads 19 are bent and formed in a gull-wing shape. Thus, the TSOP IC 29 according to the configuration shown in FIG. 1 is manufactured.

According to the above-described embodiment, the following effects can be obtained. In molding the resin-sealed body of the TSOP IC, by regulating the position of the tab with the position regulating convex portion, it is possible to prevent the resin injected into the cavity from floating the tab, so that the tab moves freely. The displacement of the tab, the exposure of the wire from the resin sealing body, and the short-circuit failure of the wire with the pellet can be avoided beforehand.

As described above, the thickness of the TSOP IC can be further reduced, and the quality of the TSOP IC can be further improved.

The position restricting convex portion for preventing the tab from floating can be formed by projecting the convex portion into the cavity of the molding die for molding the resin sealing body, so that the modification of the transfer molding device can be minimized. Can be suppressed.

FIG. 7 shows a TSOP according to the second embodiment of the present invention.
-Indicates a backfilling step in an IC manufacturing method,
(A) is a side sectional view, and (b) is a front sectional view.

The second embodiment is different from the first embodiment in that a through hole 15a is previously formed in a portion of the tab suspension lead 15 facing the upper position regulating protrusion and the lower position regulating protrusion. The trace 26a and the lower trace 26b form the through hole 1
5a. According to the second embodiment, the upper trace 26a and the lower trace 26b are formed by the through holes 15a.
Is formed, the air inside the upper trace 26a and the lower trace 26b is automatically extruded during the molding of the filled resin portion 28, so that the filled resin portion 28 is inserted into the upper trace 26a and the lower trace 26b. Can be appropriately molded.

FIG. 8 shows a TSOP according to the third embodiment of the present invention.
-Indicates a backfilling step in an IC manufacturing method,
(A) is a side sectional view, and (b) is a front sectional view.

The third embodiment differs from the first embodiment in that the inner diameter of the upper mark 26a and the inner diameter of the lower mark 26b are set to be larger than the width of the tab suspension lead 15, so that the upper mark 26a and the lower mark 26a are different from each other. The point is that the side marks 26b are communicated with each other. According to the third embodiment, since the upper trace 26a and the lower trace 26b are communicated with each other, the air inside the upper trace 26a and the lower trace 26b is automatically formed when the filled resin portion 28 is molded. Therefore, the filled resin portion 28 can be appropriately molded in the upper trace 26a and the lower trace 26b.

FIG. 9 shows a TS according to another embodiment of the present invention.
4A and 4B show OP · IC, (a) is a side sectional view, and (b)
Is a front sectional view.

TSOP IC 29A according to the present embodiment
However, the difference from the TSOP IC according to the first embodiment is that the inner diameter of the upper trace 26a and the inner diameter of the lower trace 26b are set to be larger than the width of the tab suspension lead 15 and the resin in the tab suspension lead 15 The position-regulated portion used to regulate the position of the tab 16 during the molding of the sealing body 25 is removed by punching inside the upper trace 26a and the lower trace 26b, and the upper trace 26a and the lower trace 26b are made of resin. The point is that it is not backfilled by the filling section.

According to the present embodiment, the tab 16 is restricted in position by the upper position restricting convex portion and the lower position restricting convex portion, thereby preventing the tab 16 from floating. Displacement, exposure of the wire from the resin sealing body, short-circuit failure of the wire with the pellet, and the like can be avoided beforehand.

Although the invention made by the inventor has been specifically described based on the embodiment, the invention is not limited to the embodiment, and various modifications can be made without departing from the gist of the invention. Needless to say.

For example, the position restricting projections are not limited to projecting from both the ceiling surface and the bottom surface of the cavity, but may be projecting from either the ceiling surface or the bottom surface. Further, the position regulating protrusions are not limited to being provided in a pair, but may be formed in one or three or more.

In the above description, the invention made mainly by the present inventor is described in the field of application of TSO
Although the description has been given mainly of the case where the present invention is applied to a P-IC, the present invention is not limited to this. The present invention can be applied to general semiconductor devices. In particular, the present invention can be applied to a semiconductor device having a thin resin-sealed package to obtain excellent effects.

[0044]

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

When molding the resin sealing body, the position of the tab is regulated by the position regulating projection, so that the tab can be prevented from floating due to the resin injected into the cavity. As a result, the displacement of the tab, the exposure of the wire from the resin sealing body and the short-circuit failure of the wire with the pellet can be avoided beforehand, and the quality and reliability of the semiconductor device can be improved.

[Brief description of the drawings]

FIG. 1 is a partially cutaway perspective view showing a TSOP IC according to an embodiment of the present invention.

FIGS. 2A and 2B show a multiple lead frame used in the method of manufacturing the TSOP IC, where FIG. 2A is a partially omitted plan view and FIG. 2B is a front view.

3A and 3B show a state after a pellet and a wire bonding step, and FIG. 3A is an enlarged partially omitted plan view, and FIG.
FIG. 3A is a cross-sectional view along the line bb in FIG.

4A and 4B show a molding process of a resin sealing body, in which FIG. 4A is a partially omitted side sectional view, and FIG. 4B is a sectional view taken along line bb of FIG.

FIG. 5 shows the assembly after molding the resin sealing body;
(A) is a partially omitted plan view, (b) is a side cross-sectional view of (a), and (c) is a cross-sectional view along line cc of (a).

FIG. 6 is a partially cutaway perspective view showing a process of backfilling the position regulating protrusion mark.

FIGS. 7A and 7B show a backfilling step in a TSOP IC manufacturing method according to a second embodiment of the present invention, wherein FIG. 7A is a side sectional view, and FIG.

8A and 8B show a backfilling step in the method of manufacturing a TSOP IC according to the third embodiment of the present invention, wherein FIG. 8A is a side sectional view, and FIG. 8B is a front sectional view.

FIG. 9 is a TSOP IC according to another embodiment of the present invention.
(A) is a side sectional view, and (b) is a front sectional view.

[Explanation of symbols]

11: Multiple lead frame, 12: Unit lead frame, 13: Outer frame, 14: Section frame, 15: Tab suspension lead, 15a: Through hole, 16: Tab, 17: Dam member, 17a: Dam, 18: Inner Lead, 19: outer lead, 21: bonding layer, 22: pellet, 22
a ... bonding pad, 23 ... wire, 24 ... assembly, 25 ... resin sealing body, 26a ... upper position regulation protrusion mark (upper mark), 26b ... lower position regulation protrusion mark (lower mark),
27: molded body after resin molding, 28: filled resin part,
29: TSOP IC (semiconductor device), 29A: TSO
P · IC (semiconductor device), 30: transfer molding device, 31: upper die, 32: lower die, 33: cavity, 3
3a: upper mold cavity concave part, 33b: lower mold cavity concave part, 34: pot, 35 ... plunger, 36 ... cul, 37 ... runner, 38 ... gate, 39 ... escape concave part, 4
0a: Upper position regulating protrusion, 40b: Lower position regulating protrusion,
41 ... resin.

Claims (7)

[Claims] 1. A semiconductor pellet, a tab to which the semiconductor pellet is bonded, a plurality of inner leads connected to each outer lead and electrically connected to the semiconductor pellet, a semiconductor pellet, a tab and each inner lead. In a semiconductor device comprising: a resin sealing body for sealing a lead with a resin; A semiconductor device characterized by being formed on at least one main surface and having the position control protrusion mark back filled with a filling resin portion. 2. The semiconductor device according to claim 1, wherein the position regulating protrusion mark is formed only on one main surface of the resin sealing body. 3. A semiconductor pellet, a tab to which the semiconductor pellet is bonded, a plurality of inner leads connected to the respective outer leads and electrically connected to the semiconductor pellet, a semiconductor pellet, a tab and each inner lead. In a semiconductor device comprising: a resin sealing body for sealing a lead with a resin; wherein a position regulating protrusion mark is formed on the resin sealing body by a position regulating protrusion that regulates the position of the tab during molding of the resin sealing body. A semiconductor device, which is formed and has a position-regulated portion remaining at the bottom of a position-regulating convex mark removed to remove the position-regulating convex mark. 4. The resin sealing body according to claim 1, wherein the position regulating protrusion mark is formed at an opposing position on a pair of opposing main surfaces of the resin sealing body.
3. The semiconductor device according to claim 1. 5. The method for manufacturing a semiconductor device according to claim 1, further comprising a step of molding the resin sealing body by filling a molding resin into a cavity of a molding die. In the method of manufacturing a semiconductor device provided, at least one main surface of the inner surface of the cavity is provided with a position restricting convex portion for restricting the position of the tab, and the resin sealing body molded by the cavity is provided. Wherein the resin is filled into the position-regulating protrusion mark formed by the position-controlling protrusion, and the position-controlling protrusion mark is back-filled by the filled resin portion. 6. The position control protrusion mark penetrates the resin sealing body, and when the resin is filled into the position control protrusion mark, air in the position control protrusion mark is automatically extruded. The method for manufacturing a semiconductor device according to claim 5, wherein: 7. The method for manufacturing a semiconductor device according to claim 3, wherein the resin sealing body is molded by filling a molding resin into a cavity of a molding die. In the method for manufacturing a semiconductor device, a position regulating protrusion for regulating the position of the tab is projected from an inner surface of the cavity, and the position regulating protrusion is formed on the resin sealing body molded by the cavity. A method for manufacturing a semiconductor device, comprising: removing a position-regulated portion remaining at a bottom of a position-regulating convex mark formed by a portion.