JPH07297339A - Semiconductor device and manufacture thereof - Google Patents

Abstract

PURPOSE:To reduce the burr between leads and to decrease the remaining of the bur between the leads only with die-bar cutting by increasing the distance between the outside of a resin package and a tie bar slightly larger than the clearance between the outside of the resin package and a tie-bar cutting punch, and bringing the tie bar close to the resin package. CONSTITUTION:The burr between leads is constituted so that the burr is wider than the cutting width E of a tie bar 4 on the side of a package 7 and smaller than the cutting width E of the tie bar 4 at the side of the tie bar 4. Therefore, when the tie bar 4 is cut, the burrs between the leads in a large width part 20 and a small width part 21 and the tie bar 4 are punched at the same time by providing a tie-bar puch to the position of the large width part 20. The bur between the leads generated at the side surface of a root lead 6 can be positively removed. Furthermore, the burr between the leads generated at the side surface of the package is made small by suitably setting the clearance between the tie-bar punch and the package 7, and the burr between the leads can be removed in the tie-bar cutting step.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to improvements in a semiconductor device and its manufacturing method.

[0002]

2. Description of the Related Art Conventionally known devices of this type and manufacturing methods thereof are shown in FIGS. In the figure, 1 is a lead frame, 2 and 3 are a pair of lead frames constituting the frame, 4 is a tie bar connecting the pair of lead frames 2 and 3, and 5 is a plurality of external parts connected to the tie bar 4. Lead, 6 is this external lead 5
A root lead 7 connected to the tie bar 4 is a package for resin-sealing a semiconductor chip, and is formed at a position surrounded by the lead frames 2 and 3 and the tie bar 4.

Reference numeral 8 is a lead gap formed in the space between the tie bar 4, the root lead 6 and the package 7. Reference numeral 9 is a deburring punch for removing the lead gap 8 and a clearance B between the tie bar 4 and the package. A clearance C is provided between the tie bar 4 and the base lead 6, and a clearance D is provided between the base lead 6 and the tie bar 4. The reference numeral 10 denotes the remaining burrs on the package 7 side after the deburring punch 9 is removed, and the reference numeral 11 denotes the burrs remaining on the root lead 6 side.

In the device constructed as described above,
The molding (resin encapsulation) process-the lead deburring process-the surface deburring process-the lead processing (tie bar cutting) process. During this process, after the resin sealing process, a lead inter-burr 8 is always generated between the tie bar 4, the root lead 6, and the package 7. Therefore, the deburring punch 9 as shown in FIG. 10 removes the inter-lead burr 8.

By the way, the deburring punch 9 is shown in FIGS.
As described above, a clearance B is provided between the lead frame 1 and the tie bar 4, a clearance C is provided between the tie bar 4, and the root lead 6. Compensating for each variation in molding tolerance of No. 7. For this reason, the deburring punch 9
When removing the inter-lead burr 8, the remaining burr 10 and 11 is left between the package 7 and the root lead 6, respectively.
Will occur.

[0006]

Since the conventional semiconductor device and the manufacturing method thereof are as described above, when burrs are formed between the tie bar, the root lead and the package, the burrs are removed in the deburring process. Since the package is made of resin, it is possible to reduce the clearance between the package and the deburring punch, and it is relatively easy to reduce the burr on the side surface of the package. It is difficult to reduce the clearance between the picking punch and the root lead, and burrs are left on the sides of the root lead, and the burrs must be removed manually, which increases the number of work processes. However, there is a problem that the productivity is significantly reduced.

The present invention has been made to solve the above problems, and an object of the present invention is to obtain a semiconductor device and a manufacturing method thereof in which the removal process of the flash residue can be eliminated.

[0008]

In the semiconductor device according to the first aspect of the present invention, in a semiconductor device having a tie bar which is cut after a semiconductor chip is resin-sealed in a lead frame, the lead frame is outside a resin package. In this resin package, the tie bar is brought close to the resin package so that the distance between the outside of the resin package and the tie bar is slightly larger than the clearance between the outside of the resin package and the tie bar cut punch.

In the semiconductor device according to the second invention, the distance between the outer side of the resin package of the semiconductor device according to the first invention and the tie bar is 0.3 mm or less.

In the method of manufacturing a semiconductor device according to the third aspect of the present invention, the distance between the outer side of the resin package and the tie bar is slightly larger than the clearance between the outer side of the resin package and the tie bar cut punch when the resin is sealed. The step of placing the semiconductor chip on the lead frame on which the tie bar is formed and resin-sealing, and the step of simultaneously removing the flash between the outside of the resin package and the tie bar and the tie bar of the lead frame with the tie bar cut punch described above. And ,.

In the method of manufacturing a semiconductor device according to the fourth aspect of the present invention, the distance between the outer side of the resin package and the tie bar is 0.3 mm or less when resin-sealed in the method of manufacturing the semiconductor device according to the third aspect. The tie bar is formed so that

[0012]

The semiconductor device configured as in the first invention is
Since the tie bar is close to the package, the lead-to-lead flash does not become large, and the lead-to-lead flash remains less by simply performing the tie-bar cut.

In the semiconductor device constructed according to the second aspect of the invention, since the tie bar is close to the package by 0.3 mm or less, burrs remaining on the side surface of the package and the root lead are extremely small only by performing the tie bar cut. And has a good appearance.

In the method of manufacturing a semiconductor device having the structure according to the third aspect of the present invention, since the tie bar is close to the package, the lead burrs do not become large, and the tie bar cut is simply performed to remove the lead burrs. Therefore, the tie bar cutting and the deburring can be performed simultaneously in one step.

In the method of manufacturing a semiconductor device configured as the fourth invention, since the tie bar is close to the package by 0.3 mm or less, the tie bar is simply cut.
The package can have a good appearance.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be described below with reference to FIGS.
Described in. In the figure, 20 is a large portion that opens with an opening width F that is wider than the tie bar cut width E, and is formed only on the outer side of the package 7 close to the package 7 and has a thickness G on the tie bar 4 side. Has been formed.

Reference numeral 21 denotes a small width portion which is formed continuously with the wide portion 20 up to the position of the tie bar 4, and has an opening width H narrower than the cut width E of the tie bar 4. In addition,
An opening 22 is formed by 20 and the small width portion 21. Reference numeral 23 denotes a step portion formed on the root lead 6 by the wide portion 20 and the small width portion 24.
Is a projection dimension J formed in the opening 22 and corresponding to the step 23.
It is a lead gap that causes the collar 25 of the.

In the one constructed as described above,
The lead interval burr 24 is the tie bar 4 on the package 7 side.
Is larger than the cut width E of the tie bar 4 and smaller than the cut width E of the tie bar 4 on the tie bar 4 side, and when the tie bar 4 is cut, a tie bar punch (not shown) is positioned at the position of the wide portion 20. By installing up to 20
And lead burrs 24 in the narrow width portion 21 and the tie bar 4 are punched at the same time, and lead burrs are generated on the side surface of the root lead 6.
24 is surely removed.

The lead burrs 24 formed on the side surface of the package 7 can be reduced by appropriately setting the clearance between the tie bar punch and the package 7, and the lead burrs 24 can be removed at the same time in the tie bar cutting process. In particular, the thickness G of the large part 20 is 0.3 mm, and the step 23
Good results could be obtained with the protrusion size J of 0.5 mm.

4 to 5 show another embodiment of the present invention, 30 is a tie bar provided close to the package 7, 31 is a tie bar cut width E in the package 7.
An opening portion 32 having an opening width F having a wider width than the opening portion 32 is a lead gap formed in the opening portion 31.

In this structure, the tie bar punch (not shown) is punched to the position of the opening 31 as shown in FIG. become.

[0022]

As described above, in the semiconductor device constructed as in the first invention, since the tie bar is close to the package, the lead burrs do not become large, and the tie bar cut is simply performed. There is less space left,
High productivity and low cost.

In the semiconductor device constructed as in the second invention, since the tie bar is close to the package by 0.3 mm or less, the burrs left on the side surface of the package and the root lead are extremely small only by performing the tie bar cut. It has a good appearance, is inexpensive, and has a high commercial value.

In the method of manufacturing a semiconductor device constructed as the third invention, since the tie bar is close to the package, the lead burrs do not become large, and the tie bar cut is simply performed to remove the lead burrs. Therefore, the tie bar cutting and the deburring can be performed simultaneously in one step, the manufacturing steps are reduced, and the productivity is improved.

In the method of manufacturing a semiconductor device configured as in the fourth invention, since the tie bar is close to the package by 0.3 mm or less, the tie bar is simply cut.
A package with a good appearance can be obtained, and the productivity is improved while increasing the commercial value.

[Brief description of drawings]

FIG. 1 is a plan view showing an embodiment of the present invention.

FIG. 2 is an enlarged plan view of a main part of the embodiment shown in FIG.

FIG. 3 is an enlarged plan view of an essential part after the tie bar is cut in the embodiment of FIG.

FIG. 4 is a plan view showing another embodiment of the present invention.

5 is an enlarged plan view of an essential part of the embodiment of FIG.

FIG. 6 is a plan view showing a conventional lead frame.

FIG. 7 is a plan view of a conventional lead frame after being molded.

FIG. 8 is an enlarged plan view of a main part of a conventional lead frame.

FIG. 9 is a sectional view of a main part of a conventional lead frame.

FIG. 10 is a fragmentary sectional view showing a conventional deburring process of a lead frame.

11 is a sectional view taken along line XI-XI of FIG.

FIG. 12 is an enlarged plan view of an essential part of a conventional lead frame after deflashing.

[Explanation of symbols]

1 lead frame, 4 tie bar, 5 external lead, 6 root lead, 7 package,
22 openings, 24 lead spacing, 30 tie bars.

Claims (4)

[Claims] 1. A semiconductor device having a tie bar cut into a lead frame after resin-sealing a semiconductor chip, wherein the lead frame is outside the resin package, the tie bar is provided in the resin package, and the outside and the tie bar of the resin package are provided. The semiconductor device is characterized in that the distance is slightly larger than the clearance between the outside of the resin package and the tie bar cut punch. 2. The semiconductor device according to claim 1, wherein the distance between the outside of the resin package and the tie bar is 0.3 mm or less. 3. A semiconductor chip on a lead frame having a tie bar formed so that the distance between the tie bar and the outside of the resin package when sealed with resin is slightly larger than the clearance between the outside of the resin package and the tie bar cut punch. A method of manufacturing a semiconductor device, comprising the steps of: mounting and resin-sealing, and the step of simultaneously removing the burr between the outside of the resin package and the tie bar and the tie bar of the lead frame with the tie bar cut punch. 4. The method of manufacturing a semiconductor device according to claim 3, wherein the tie bar is formed such that the distance between the outer side of the resin package and the tie bar is 0.3 mm or less when the resin is sealed. .