JPH10116950A - Manufacturing method of semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve productivity by coating a water-soluble resin only to each lead forming a lead frame, resin molding each lead to be connected to the semiconductor element, and removing burn from the mold resin by using a low water pressure nozzle for the water-soluble resin. SOLUTION: A lead frame connects a lead 1 to a tie bar 2. A water-soluble resin 3 is coated only from a end portion of a region of resin mold of lead 1 to the tie bar 2 and its surroundings. Each lead 1 for connecting by bonding to the semiconductor element is attached to a die, and molding is performed by a mold resin 4. A mold resin 4 leaks out from the die to a space between leads 1 and burr 4' but this burr 4' flows between the leads 1 and is stopped by the tie bar 2. Thereafter, the water-soluble resin 3 coated in the vicinity of each lead 1 is removed by using a low water pressure nozzle 5 and the burr 4' can be eliminated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method of manufacturing a semiconductor device, and more particularly to a method of manufacturing a resin-sealed semiconductor device.

[0002]

2. Description of the Related Art Conventionally, in the production of such a resin-sealed type semiconductor device, the occurrence of burrs at the time of resin-sealing has been a problem, and various proposals have been made to solve the rollers.

FIGS. 3A to 3D are cross-sectional views of a semiconductor device shown in the order of steps for explaining an example of the related art. First, as shown in FIG. 3A, a semiconductor element (pellet) 7 is mounted on an island 8 of a lead frame,
The lead 1 and the pellet 7 are bonded by a bonding wire 9. Next, the semi-finished product that has been subjected to the bonding connection step is mounted inside the resin sealing mold 6.
The tie bar 2 is formed at right angles to the lead 1.

Next, as shown in FIG. 3 (b), a molding resin 4 is injected into a resin sealing mold 6, and the resin is sealed. At this time, the molding resin 4 is engaged with the tie bar 2.

[0005] Next, as shown in FIG. 3 (c), the resin-sealed semi-finished product is taken out of the resin-sealing mold 6, and the resin is deburred. That is, the burrs 4 ′ adhered between the leads 1 are removed by using the water pressure from the hydraulic deburring nozzle 5.

Further, as shown in FIG. 3D, the burrs 4 'between the leads 1 reaching the tie bars 2 are removed.

FIGS. 4A to 4D respectively show FIGS.
It is a top view of a semiconductor device shown in order of a process corresponding to (d). As shown in FIGS. 4A to 4D, the manufacturing process is as described above with reference to FIGS. 3A to 3D. After resin sealing, burrs 4 ′ are generated between the leads 1. , Are removed by a hydraulic nozzle 5.

There are various methods other than the deburring method described above, and for example, there is an example described in Japanese Patent Application Laid-Open No. 4-38858.

FIG. 5 is a plan view of a lead frame in a semiconductor device for explaining another example of the related art.
As shown in FIG. 5, the lead frame of the semiconductor device is an improved example of the semiconductor device manufactured according to FIG. 3 described above, and uses a coating pattern 10. That is, the leads 1 are arranged around the die pad (island) 8, and the coating pattern 10 is formed around the resin-molded outer shell 11, and at a portion other than the leads 1. By forming this coating pattern 10 in advance,
The burrs between the leads 1 are stopped.

However, in this case, since the resin bite between the leads 1 is strong, it is not possible to completely remove the burr of the resin, and the resin residue is generated. In order to improve the resin residue, the following method has been adopted.

FIG. 6 is a perspective view of a part of a lead frame of a semiconductor device for explaining another conventional example. As shown in FIG. 6, this lead frame is obtained by forming the coating pattern 10 of FIG.
In short, in this example, by forming the tie bar with the water-soluble resin 3, the resin residue is reduced.

[0012]

In the above-described conventional method for manufacturing a semiconductor device, particularly in the example shown in FIG. 6, the portion where the tie bar is changed to a water-soluble resin can easily remove burrs. The side portion has a disadvantage that resin residue is generated. That is, the force of the mold resin biting into the lead is strong, and even if the resin residue is eliminated only in the tie bar portion, it is not effective in removing burrs.

Further, in the example of applying resin between the leads as shown in FIG. 5, there is a disadvantage that the applied resin expands due to the heat of the mold at the time of sealing the resin and deforms the leads. For example, if a water-soluble resin is applied between the leads by screen printing, the resin expanded by heat goes in the lead direction because there is no gap, and the leads themselves are deformed.

Further, even if such a water-soluble resin is applied between the leads by screen printing, the space between the leads is not buried at the same height as the leads, and the resin leaks from the gap at the time of resin sealing. The reason is that it is difficult to obtain the precision of the resin film thickness by screen printing. In other words, in order to form a space between the leads without any gaps, the resin film thickness must be increased. In this case, the resin that has come out higher than the leads is pressed by a mold, and the leads are similarly deformed. become.

An object of the present invention is to provide a method of manufacturing a semiconductor device using such a water-soluble resin, which can remove burrs of a mold resin at a low water pressure and can improve productivity.

[0016]

According to a method of manufacturing a semiconductor device of the present invention, a step of coating a water-soluble resin only on each lead forming a lead frame, and a step of coating a semiconductor element and each of said leads for connecting to the semiconductor element The method includes a step of resin-molding the leads, and a step of subsequently removing the water-soluble resin of each of the leads using a low-pressure nozzle.

Further, the water-soluble resin in the present invention comprises:
The lead portion from the end of the resin molding region to the tie bar is formed to be coated.

Further, the water-soluble resin in the present invention is formed so as to coat a predetermined portion of each of the leads to a thickness of about 10 μm using screen printing.

[0019]

Next, embodiments of the present invention will be described with reference to the drawings.

FIGS. 1A to 1D are sectional views of a semiconductor device shown in the order of steps for explaining an embodiment of the present invention. As shown in FIG. 1A, in manufacturing the semiconductor device according to the present embodiment, a lead frame in which inner leads (leads) 1 are connected by tie bars 2 is used.

Next, as shown in FIG. 1B, a water-soluble resin 3 is coated only around the lead 1. In particular, the water-soluble resin 3 is applied to the lead 1 from the end of the resin molding region to the tie bar 2 in the lead 1.

Further, as shown in FIG. 1C, a semiconductor element (not shown) and leads 1 for bonding connection to the semiconductor element are mounted on a mold (not shown). Mold. At this time, the mold resin 4 leaks out of the mold into the space between the leads 1 to form burrs 4 ′. The burrs 4 ′ flow between the leads 1 and are stopped by the tie bars 2. That is, the burr 4 ′ does not flow because the water-soluble resin 3 exists on the lead 1.

Thereafter, as shown in FIG. 1D, the water-soluble resin 3 applied around each lead 1 is removed by using a low water pressure deburring nozzle 5. At the same time, the burrs 4 ′ are not attached to the periphery of the lead 1 and are removed by the low-pressure deburring nozzle 5. Accordingly, it is possible to eliminate the side surface of the lead 1, that is, the burr 4 ′ which is a resin residue between the leads 1.

FIGS. 2A to 2D respectively show FIGS.
It is a top view of a semiconductor device shown in order of a process corresponding to (d). As shown in FIGS. 2A to 2D, the manufacturing process is as described above with reference to FIGS. 1A to 1D. Here, the water-soluble resin 3 is applied to a predetermined portion from the edge to be sealed to the tie bar 2 as described above. Or using screen printing. In particular, when applying using screen printing, 10 μm is applied to a predetermined portion of each lead 1 in consideration of thermal expansion.
m.

According to the above-described embodiment, by coating a predetermined portion of the lead with a water-soluble resin,
Since the bite of the mold resin can be performed not on the lead itself but on the water-soluble resin, the resin residue can be reliably prevented even at a low water pressure.

[0026]

As described above, in the method of manufacturing a semiconductor device according to the present invention, only the leads are coated with a water-soluble resin, and after resin molding, the water-soluble resin of each lead is removed using a hydraulic deburring nozzle. By removing, there is an effect that burrs, which are resin residues, can be reliably and easily removed. That is, since the side surfaces of the leads are also coated with the water-soluble resin, they can be easily removed at a low water pressure.

Further, a method of manufacturing a semiconductor device according to the present invention
By not filling the space between the leads with the water-soluble resin, even if the water-soluble resin is pressed by the mold, or if the water-soluble resin expands due to the heat of the mold at the time of resin sealing, the direction of the gap between the leads can be reduced Therefore, there is an effect that the lead is not deformed.

Further, the method of manufacturing a semiconductor device according to the present invention has an effect that the resin does not leak beyond the tie bar during resin sealing as compared with a conventional semiconductor device in which the tie bar itself is changed to a water-soluble resin. There is. In particular, applying a water-soluble resin to the tie bar by screen printing is
Since precision such as film thickness adjustment is required, resin wetting is prevented by using a conventional structure in which leads and tie bars are connected (integrated).

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a semiconductor device shown in the order of steps for describing one embodiment of the present invention.

FIG. 2 is a plan view of the semiconductor device shown in a process order corresponding to FIG. 1;

FIG. 3 is a cross-sectional view of a semiconductor device shown in the order of steps for explaining an example of the related art.

FIG. 4 is a plan view of the semiconductor device shown in a process order corresponding to FIG. 3;

FIG. 5 is a plan view of a lead frame in a semiconductor device for explaining another conventional example.

FIG. 6 is a perspective view of a part of a lead frame of a semiconductor device for explaining another conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Lead 2 Tie bar 3 Water-soluble resin 4 Mold resin 5 Hydraulic deburring nozzle

Claims (3)

[Claims] 1. A step of coating only a lead forming a lead frame with a water-soluble resin; a step of resin-molding a semiconductor element and each of the leads for connecting to the semiconductor element; Removing the water-soluble resin using a low water pressure nozzle. 2. The method of manufacturing a semiconductor device according to claim 1, wherein said water-soluble resin is coated on a lead portion from an end of said resin molding region to a tie bar. 3. The method according to claim 1, wherein the water-soluble resin is coated on a predetermined portion of each of the leads to a thickness of about 10 μm using screen printing.