JPS60138949A - Lead frame for semiconductor device - Google Patents

Abstract

PURPOSE:To enable to scarcely generate a gate remainder by a method wherein a notch is provided at a position corresponding to a gate for resin sealing located at the side end of one way on the inner side of one of two lead frames. CONSTITUTION:This semiconductor device has a bed part 3, whereon a semiconductor element pellet (has not been shown in the diagram) is to be mounted in the central part between mutually parallel two lead frames 2', and plural lead parts, which have been provided in the peripheral parts of the bed part 3 and have been formed in a form spreading radially from the vicinity of the bed part 3, in the same manner as the conventional one, but a rectangular notch 12 is provided at a position corresponding to a gate for resin sealing located at the side end of one way on the inner side of one way of the lead frames 2' in this semiconductor device. The size of the notch 12 is the bigger the better from an aim of enabling the adhesion of a gate part resin 6' to lower, but the size is formed in such a way to have a width and a depth of one-second or thereabouts of the width of the frame 2' in order to maintain the strength of the frame 2'. In case a resin sealing was performed, the gate part resin 6' can be easily removed by applying a mechanical external force without generating a gate remainder, because there exists no lead frame 2' to cause an adhesion on the upper face of the point 6'a of the gate part resin 6'.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a lead frame for a semiconductor device, and is particularly used for a resin-sealed semiconductor integrated circuit device.

[Technical background of the invention]

Mass production of resin-sealed (mold) type semiconductor integrated circuit devices.
It is possible to reduce the price, and is widely used as reliability has improved due to recent technological improvements.

For resin/resin sealing, a transfer molding method is usually used, which has good dimensional accuracy and good molding efficiency.

This is heated in advance with a preheater and a mold: the molding material such as plasticized epoxy resin is sprued.
, launch, and gate into the cavity in the mold for hardening. In resin sealing of a semiconductor integrated circuit device, a lead frame 1 shown in FIG. 1 is used. This is made by forming a thin metal plate of iron-nickel alloy or Konoseru metal into a predetermined pattern by machining, chiming, etc., and a semiconductor element pellet is placed in the center between two mutually parallel frames λ. It has a bed part 3 to be mounted, and a plurality of lead parts formed around the bed part 3 in a shape extending radially from the vicinity of the bed part. When using such a lead frame, the launch is arranged parallel to the frame frame λ, and the gate is arranged in a part of the frame so as to extend from the launch into the lead frame. Therefore, as shown in the perspective view of FIG. 2 and FIG. 3, which is a sectional view taken along the line A-A', the state after resin sealing is such that a frame frame is attached to the lower part of the frame side end surface ta of the resin-sealed package j. The gate part resin 6 and runner part resin 7 which are in close contact with the parts remain. After the molding is completed, the gate resin B and the runner resin 7 are removed from the lead frame/and semiconductor integrated circuit package J by applying mechanical force.

[Problems with background technology]

However, as shown in Figure 3, the tip 6a of the gate resin B is in close contact with the lead frame L, and the tip is tapered, so mechanical removal is difficult and the adhesion is strong. In this case, it is not broken at the boundary between the packages, and only the tip remains on the frame λ of the lead frame l, as shown by the intersection line Ja in FIG. Such so-called gate residue prevents the frame λ from being correctly positioned on the guide surface during processes such as lead separation by bunching and lead bending, resulting in defective products and damage to the punch. There's a problem.

[Purpose of the invention]

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a lead frame for a semiconductor device in which gate residue is less likely to occur.

[Summary of the invention]

In order to achieve the above object, in the present invention, a notch is provided inside the lead frame frame at a position corresponding to the resin sealing gate. It is less likely to leave residue.

[Embodiments of the invention]

Hereinafter, some embodiments of the present invention will be described in detail with reference to the drawings.

FIG. μ is a plan view showing a lead frame // according to the present invention. Similar to the conventional lead frame, there is a semiconductor element pellet (not shown) in the center between two parallel frame frames λ'. The bed part 3 on which the frame part' is mounted has a plurality of lead parts extending radially from the vicinity of the bed part 3 around the bed part 3. A rectangular notch >a□ is provided at a position corresponding to the stop gate.The size of this notch 12 is preferably larger for the purpose of reducing the force of applying resin to the gate.
In order to maintain the strength of the frame frame λ', it is appropriate that the frame frame λ' has a width and depth approximately equal to the width of the frame frame -'.

The perspective view of FIG. 5 and FIG. 6, which is a sectional view taken along the line B-tpr', show how such a lead frame is used to withstand resin loads. According to this, since there is no lead frame frame -' which causes close contact on the upper surface of the tip 4'a of the gate part resin 6', this gate part resin t' cannot be subjected to mechanical external force. The embodiment shown in Figure 1 has a notch on only one side of the frame λ', but the purpose of this is to improve the efficiency of the resin sealing process. de1
Even in a molding method in which resin is delivered from two launches to gates provided on both sides, notches can be provided in the frame frames on both sides so that the direction of the lead frame does not have to be reversed.

FIG. 7 is a plan view showing another embodiment of the present invention, and on the frame # there is a part t of a tie plate that connects and supports a plurality of glue dogs from a position corresponding to the resin sealing gate. It has an L-shaped notch 13 that reaches an extension of the . This notch 13 serves to facilitate the removal of the gate resin, and because the coefficient of thermal expansion of the lead frame material is smaller than that of the molding resin, it is used to cover the entire lead frame during molding.
In the above examples, the shape of the notch was all rectangular or a modification thereof, but any shape can be selected, such as one with a rounded part at the innermost part of the notch. be able to.

〔Effect of the invention〕

As described above, according to the present invention, the notch is provided at the position corresponding to the resin sealing gate at the inner end of the frame.
The number of frame parts that cause close contact during resin sealing is reduced, and the resin on the gate part after sealing can be easily and completely removed, reducing the occurrence of defects and tool damage caused by gate residue. Production efficiency can also be improved. Furthermore, a pressing jig that presses the gate resin can be inserted through the notch, and the gate resin can be removed more efficiently.

[Brief explanation of drawings]

Fig. 1 is a plan view showing a conventional lead frame for semiconductor devices, Fig. 2 is a perspective view showing resin sealing using the lead frame shown in Fig. 1, and Fig. 3 is Fig. 2. 5 is a cross-sectional view taken along the line A-A' in FIG. A perspective view showing how the process is carried out, FIG. 6 is B- in FIG.
A sectional view taken along the line B' and FIG. 7 are plan views showing another embodiment of the present invention. / , // ,, //'...Lead frame for semiconductor device 1.2. ．． 2',! ...Frame frame, 3...
Bed part, ≠... Lead part, j... Resin sealing package, t... Gate part resin, 7... Launch part resin.
r...Tights-1/2...notch, /J...L-shaped notch. Applicant's agent Inomata Affair Figure 1 Figure 2 Figure 3 Figure 41 u: / Figure 5 Figure 7 U'

Claims (1)

[Claims] / A lead for a semiconductor device, which includes a bed portion on which a semiconductor pellet is mounted, a plurality of lead portions arranged around the bed portion, and a frame supporting the 4°P portion and the lead portions. In the frame. A cutout portion is provided at a position corresponding to the resin sealing gate at the inner end of the frame (f6□1□+)
-yyv-b. 1. A lead frame for a semiconductor device according to claim 1, wherein the notch is rectangular. 1 [ 3. Extension for connecting and supporting multiple leads from the position 1□ where the notch corresponds to the resin sealing gate.
Patent claim: □ Semiconductor lead frame according to claim 7, which has an L-shape that reaches 1 part. 1: ≠, the dimensions of the notch are approximately half of one frame in both width and depth. 1. A lead frame for a semiconductor device according to claim 2.