JPH03153062A - Ic package - Google Patents

Abstract

PURPOSE:To prevent the bending of a lead induced by a reduction in a package area and external force as well by providing elasticity to a lead with its tip placed on the surface, bending the tip in U-shape and further bending the lead inward to the interior of the package. CONSTITUTION:A lead 2 of a package is cut off from a guide 6 of a lead frame. After it is cut off, the tip of the lead 2 is bent into U-shape and then the entire lead is bent downward along the package. This process makes it possible to produce an intended package 4. Since this lead 2 is along the side of the package 4, it is resistant against external forces from the side of the package and the bottom of the lead. Furthermore, since the tip of the lead bent in U-shape is elastic, the restoring force against the external forces is available.

Description

[Detailed description of the invention] [Industrial application field 1 The present invention relates to semiconductor IC packages.

[Prior Art] Conventional IC packages for surface mounting on substrates are either QFP with a gallowing shape (Figure 1) in which the lead is exposed outside, or PLCC (with lead tips bent inward into a J shape). Figure 2) was known.In Figure 1, 1 is a QFP package,
2 is a lead, 3 is a substrate, and 4 is a PLCC package.

[Problem to be Solved by the Invention 1] However, QFP packages have the problem that compared to PLCC, the mounting area is larger due to the exposed lead, and the tips of the leads are bent up and down by some external force, which causes the board There was a problem that a gap with the board was created during mounting, resulting in poor soldering. PLCC packages also have the problem of having a small contact surface with the board, which can lead to defects in soldering.As the contact surface is small, it can be bent upwards due to some kind of external pressure, creating a gap similar to QFP, which can lead to defects in soldering. Was.

In order to solve these conventional problems, the present invention aims to bend the tips of the leads into a U-shape to reduce the mounting area and to prevent the leads from being bent by external forces.

[Means to solve the problem]

In order to solve the above-mentioned problems, the IC package of the present invention has the tips of the leads made into surfaces and U-shaped tips to provide elasticity.
It is characterized by a small mounting area by bending the leads into a square shape and bending them inside the package.

[Example 1] Examples of the present invention are shown below in Figures 3 (a) to (c) and 4.
In the figure, 2 is a lead, 3 is a substrate, 5 is a package mold, 6 is a lead frame guide, 7 is a lead cutting, 8 is a lead bending mold,
9 is a lead bending type 2.

First, as an example of the manufacturing process, the node of the package is cut and separated from the guide of the lead frame as shown in Figure 3(a). Next, the tip of the lead is cut into a U shape as shown in Figure 3(b).
First, bend the entire lead downward along the package as shown in Figure 3(C). Through this process, the desired package shown in FIG. 4 can be obtained.

This lead is along the side of the package, so it is strong against external pressure from the side and from under the lead.
The tip of the lead, which is bent into a square shape, is elastic and has a restoring effect against external pressure.

[Effects of the Invention] As explained above, the IC package of the present invention has a smaller mounting area than a QFP (the lead contact area with the substrate is P
It is larger than LCC and has better soldering properties, and since the tip is U-shaped, the lead is less likely to bend due to external pressure, making soldering less likely to cause defects.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing a QFP package for explaining the present invention, and part (a) thereof is a diagram showing a state in which the leads are bent by external pressure. Figure 2 is a diagram showing a PLCC package, and its (b
) indicates that the lower point of the lead has been crushed by external pressure. FIG. 3(a) is a diagram showing a state in which the leads are separated from the lead frame. FIG. 3(b) is a diagram showing a state in which the tip of the lead is bent into a U-shape. FIG. 3(C) is a diagram showing a state in which the leads are bent along the side surface of the package. FIG. 4 is a diagram showing the completed state. QFP package lead board PLCC package package mold J-do frame guide lead cutting Lead song type l Lead song type 2 1311

Claims (1)

[Claims] (1) An IC package for sealing an IC, characterized in that the shape of the leads is bent along the side surface of the mold, and the tips of the leads are bent inward in a U-shape.