JPS5932058B2 - Manufacturing method for resin-sealed electronic components - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of manufacturing a resin-sealed electronic component, which removes pars generated during resin-sealing using a transfer method.

FIG. 1 is a perspective view showing a typical resin-sealed semiconductor device.
A semiconductor element 2 is attached to one of a group of multiple lead wires 1 by brazing or the like, and the electrodes on this element and other lead wires 1 are sealed with a resin 4 with soil connected by a thin metal wire 3. Manufactured by

As a resin sealing method for such a resin-sealed semiconductor device, there are resin sealing methods such as E-back, casting, botting, and transfer methods. Among these, the transfer resin encapsulation method is commonly used as a resin encapsulation method for semiconductor devices due to its mass productivity, workability, and low cost of materials used. The conventional method for manufacturing semiconductor devices using the transfer resin encapsulation method will be described below with reference to FIGS. 2 to 6.
This will be explained using figures.

Figure 2 is a schematic cross-sectional view showing transfer resin sealing;
The figure is a side view of the main part of Figure 2, Figure 4 is a plan view showing the semiconductor device after being sealed with transfer resin, and Figures 5 and 6 are resin seeping out from the gap in the mold (hereinafter referred to as burr). FIG. 2 is a schematic perspective view showing a conventional method for removing .

As shown in FIG. 2, the resin sealing is performed by placing the semiconductor element 2, the thin metal wire 4, and the tips of the lead wires 1 in a space 5 formed by an upper mold 6 and a lower mold T of a transfer mold (hereinafter referred to as the mold). The lead wire 1 is inserted into the mold 6 so that the part 8 including the part is located.
, 7 and injecting resin 9 into the space 5.

As shown in FIG. 3, a gap 10 is created between the lead wire 1 and the mold 6 and T that hold it, which causes a problem in the method of determining the transfer date. The injected resin 9 oozes out from these gaps 10 and forms burrs 11 as shown in FIG. This burr 11 causes poor contact between the lead wire 1 and the socket when the semiconductor device is inserted into a socket when the semiconductor device is used, resulting in deterioration of the quality of the semiconductor device. As shown in FIG. 5, the particles are removed by shot blasting from a nozzle 12 using walnut grains or glass beads 13, or by cutting with a cutter 14 as shown in FIG. However, the method of removing burrs 11 using shotplast has a short lifespan of the walnut grains and glass beads 13, increases the cost of materials because they are used in large quantities, and worsens the working environment due to the scattering of dust generated during spraying. Processing equipment and the like are required, and the labor and equipment costs required for this are enormous.

Furthermore, the oil and fat contained in the walnut grains caused an oil film to form on the surface of the lead wire 1, making it difficult for solder to adhere to the lead wire 1. On the other hand, the method for removing burrs 11 by cutting with the cutter 14 requires highly accurate positioning of the semiconductor device to be cut for each lead wire 1 with respect to the cutting edge of the cutter 14. One cutter on one lead wire
The cutting edge of No. 4 caused scratches, resulting in a deterioration in the quality of the semiconductor device. Furthermore, since the cutting edge of the cutter 14 must be kept sharp at all times, the cost of repairing equipment and jigs and tools due to wear and tear on the cutter 14 increases. Further, in the burr removal method using the cutter 14, the burr 11 between the lead wires 1 is removed, but the burr 11 attached around the lead wire 1 is difficult to remove. Of course, it is essentially desirable to eliminate the occurrence of burrs 11, and by eliminating gaps by zeroing the fitting tolerance between the upper and lower molds 6 and 7 of the transfer mold and the lead wires 1, it is possible to Although the occurrence of river 1 can be prevented, in general, from the viewpoint of productivity, a large number of semiconductor devices are molded at once, so a large number of lead wires 1 are clamped, resulting in variations in the wire diameter (dimensions) of lead wires 1. In addition, the surface of the lead wire 1 is plated to improve brazability with the semiconductor element, and there are variations in the thickness of the plating, and there are also variations in the precision of the mold itself, so it is impossible to This is something that cannot be achieved on a commercial scale.

Therefore, it is impossible to completely eliminate the occurrence of burrs 11, and it is also impossible to omit deburring. The present invention has been made in consideration of the above points, and provides a method for directly pressing the burr with an elastic body such as rubber and removing the burr by the deformation force of the elastic body.

This invention will be explained below. FIG. 7 is a perspective view showing an embodiment of the present invention, and FIG. 8 shows a semiconductor device with burrs on top.
It is an enlarged front view of the main part showing the state where it is bitten between the lower rolls. In these figures, the roll mechanism 1 rotates in a mutually biting direction (arrow R in the figures) with an upper roll Al5 and an upper roll 17 whose outer periphery is in close contact with a rubber lining made of an elastic material Al6 such as urethane rubber. and a rigid lower roll Al8. Furthermore, the roll mechanism in the opposite combination to the roll mechanism 1 described above rotates in the mutually interdigitating direction (arrow R in the figure), and includes a rigid earth roll Bl9, a lower roll B2O, and an elastic material such as urethane rubber on the outer periphery thereof. The lower roll 22 is in close contact with the body B2l. The roll mechanism 1 and the roll mechanism are arranged in series with each other, and both are constantly rotated in the R direction by a drive mechanism (not shown). Now, after the transfer resin has been bonded, the semiconductor device shown in FIG. 1 (in the direction of arrow L1 in the figure), the semiconductor device is bitten between the soil roll 17 and the lower roll Al8, and the elastic body Al6 deforms as shown in FIG. A deforming force P of the body Al6 is applied, and the burr 11 separates from the lead wire 1 due to the frictional force caused by this deforming force P. That is, lead wire 1
The burr 11 on the upper half of is removed. Further, at that point, the burrs 11 between the lead wires 1 are also removed by the same deforming force P. Next, when it is sent to the roll mechanism (in the direction of arrow L2 in the figure), the burr 1 on the lower half of the lead wire 1 is
1 is removed, and the burr 11 on the lead wire 1 can be completely removed. That is, the burr 11 can be scraped off by the frictional force caused by the deformation force P of the elastic bodies Al6 and B2l that are in close contact with the rotating roll. In the above embodiment, two sets of roll mechanisms were used, but two or more sets of roll mechanisms may be used depending on the size of the lead wire, the occurrence of resin fringing, the type of resin, etc. .

Furthermore, the roll mechanism is not necessarily required, and the same effect can be obtained by inserting a lead wire with burrs between the upper and lower mechanisms using an elastic body and a rigid flat part and compressing it once or several times. is obtained. Further, as shown in FIG. 9, in the case of a semiconductor device having one lead wire 1, since the lead wire 1 rotates between one set of roll mechanisms 1, one set of roll mechanisms may be used. Further, depending on the type of resin, the effect may be even greater if the method of the present invention is used after cracking the burr 11 in advance. As explained in detail above, this invention does not require shot blasting materials as in the past, and therefore there is no need for dust scattering or dust treatment equipment, and there is no need for jigs and tools as in the case of a conventional cutter. There will be no breakage, and the life of the jigs and tools will be greatly extended.

Furthermore, the deburring work according to the present invention is a continuous work, and positioning for deburring becomes easy. Furthermore, according to the method of the present invention, there is no damage to the lead wire surface or resin surface caused by shot blasting, and there is no drawback such as difficulty in adhering solder to the lead wire due to the oils and fats mentioned above. An improvement in yield can be expected.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing a normal four-stop type semiconductor device, Fig. 2 is a schematic sectional view showing a transfer resin seal, Fig. 3 is a sectional view of the main part of Fig. 2, and Fig. 4 is a schematic sectional view showing a transfer resin seal. 5 and 6 are respectively schematic perspective views showing a conventional deburring method, FIG. 7 is a perspective view showing an embodiment of the present invention, and FIG. The figure is an enlarged front view of the main part showing a state in which burrs of the semiconductor device are bitten between the upper and lower rolls, and FIG. 9 is a perspective view showing the semiconductor device with one lead wire. In the figure, 1 is a lead wire, 4 is a resin, 11 is a burr, 15 is an upper roll A, 16 is an elastic body A, 17 is an upper roll, 18 is a lower roll A, 19 is a soil roll B, 20 is a lower roll Bl2l
The elastic body Bl22 is the lower roll.

Claims (1)

[Scope of Claims] 1. A resin-sealed electronic component in which an element body and a connection portion of an external lead wire electrically connected to the element body are sealed with a resin, in which the element body extends from the resin-sealed portion. The resin-sealed electronic component is characterized in that the resin film oozing out onto the external lead wire is pressurized by an elastic body, and the oozing resin film is removed by the deformation force of the elastic body. Production method. 2. A patent characterized in that the pressure on the resin film is applied between an upper roll equipped with an elastic body that is in close contact with the roll surface and a rigid lower roll that rotates in a direction that engages the upper roll. A method for manufacturing a resin-sealed electronic component according to claim 1.