JPH03201469A - Semiconductor device - Google Patents

Abstract

PURPOSE:To obtain a semiconductor device high in reliability, where cracks are prevented from occurring in sealing resin in an infrared reflow soldering process by a method wherein the sealing resin is dyed in color that hardly absorbs infrared energy and leads are dyed in color that is liable to absorb infrared energy. CONSTITUTION:Sealing resin is dyed in color that hardly absorbs infrared energy or in white 1 and leads are dyed in color that is liable to absorb infrared energy or black 2. When a semiconductor device is mounted on a circuit board through an infrared reflow method, only the leads become high in temperature before the sealing resin becomes high in temperature, solder is fused to solder the leads as the sealing resin is white that hardly absorbs infrared energy and the leads are black which is liable to absorb infrared. The sealing resin does not become so high in temperature and is protected against cracks caused by internal steam contained in resin.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a resin-sealed semiconductor device, and in particular, the sealing resin has a white color that does not easily absorb infrared energy, and the external lead terminal has a color that absorbs infrared energy. The present invention relates to a semiconductor device that has a black color that is easy to clean.

[Conventional technology]

In recent years, the number of semiconductor devices that can be mounted on one circuit board (
As a mounting method for increasing the mounting density (hereinafter abbreviated as mounting density), there is a method called surface mounting.

FIG. 2 is a perspective view of a conventional resin-sealed semiconductor device for surface mounting (hereinafter referred to as a surface-mounted semiconductor device). As shown in the figure, in this surface-mounted semiconductor device, the color (1a) of the sealing resin of the semiconductor device is almost black, and the color (2a) of the external lead terminals (hereinafter referred to as leads) is that the leads are soldered. Because it was plated, it was composed of a mouse color.

One of the methods for mounting a surface-mounted semiconductor device on a circuit board is a mounting method called infrared reflow.

This is a method in which a paste-like solder is applied onto the copper pattern of a circuit board, and the entire structure, with a surface-mounted semiconductor device mounted thereon, is soldered by passing it through an infrared reflow oven. At this time, in order to reliably solder the leads of the surface-mounted semiconductor device and the copper pattern of the circuit board, it is necessary to set the temperature of the infrared reflow oven to a temperature high enough to melt the solder. At that time, since the color (1a) of the sealing resin of the semiconductor device is black, it easily absorbs infrared energy, and the temperature of the sealing resin together with the leads becomes high and the internal water vapor contained in the sealing resin seals the device. Cracks may form in the resin, reducing reliability.

Furthermore, in order to reduce the internal water vapor of the sealing resin, it is necessary to store the surface-mounted semiconductor device at high temperature for a long time before performing infrared reflow.

[Problem to be solved by the invention]

Conventional surface-mounted semiconductor devices were configured as described above, so when they were mounted on a circuit board using infrared reflow, the sealing resin absorbed infrared energy and became hot, causing internal water vapor to cause sealing. There are other problems such as cracks in the resin, reducing reliability, and surface mount semiconductor devices having to be stored at high temperatures for long periods of time before infrared reflow to reduce the amount of water vapor inside the sealing resin. Ta.

This invention was made to solve the above-mentioned problems, and it does not require long-term storage at high temperatures before performing infrared reflow, and it is also reliable in that it does not get into the sealing resin during infrared reflow. The purpose is to obtain a semiconductor device with high performance.

[Means to solve the problem]

In the semiconductor device according to the present invention, the color of the sealing resin is a color that makes it difficult to absorb infrared energy, and the color of the leads is a color that makes it difficult to absorb infrared energy.

[Effect]

In the semiconductor device of this invention, the color of the sealing resin is changed to a color that makes it difficult to absorb infrared energy, and the color of the leads is made to a color that makes it difficult to absorb infrared energy, so that the semiconductor device can be reflowed by infrared rays without being stored at high temperatures for a long time. The sealing resin will not crack even during the process, improving reliability.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings. 1st
In the figure, (1) indicates that the sealing resin is white, which does not easily absorb infrared energy, and (2) indicates that the lead color is black, which does not easily absorb infrared energy.

Next, the operation will be explained. When a semiconductor device is mounted on a circuit board using the infrared reflow method, the encapsulating resin is white, which does not easily absorb infrared energy, and the leads are black, which absorbs infrared energy easily. becomes hot and the solder melts and is soldered.

Therefore, since the color of the sealing resin is white, which does not easily absorb infrared energy, it does not get very hot, the sealing resin does not crack due to internal water vapor contained in the resin, and the inside of the sealing resin There is no need for long-term storage at high temperatures to reduce water vapor.

Note that in the above embodiment, the surface mount type semiconductor device is F P
(Quad Flat Package) type is shown, but any type that can be surface mounted may be used. In addition, the white color (1
) and black (2), which hardly absorbs infrared rays, may be relative to each other, or white and black may be other colors of the same family.

〔Effect of the invention〕

As described above, according to the present invention, the color of the sealing resin is made to be a color that does not easily absorb infrared energy, and the color of the leads is made to be a color that does not easily absorb infrared energy. This has the effect of eliminating the need for the sealing resin and providing a highly reliable sealing resin that does not crack even after infrared reflow.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing a semiconductor device according to an embodiment of the present invention, and FIG. 2 is a perspective view showing a conventional semiconductor device. In the figure, (1) indicates white, which is difficult to absorb infrared energy, and (2) indicates black, which is easy to absorb infrared energy. Embedded by Masuo Oiwa Diagram 1 Procedure Amendment (Voluntary) April 6, 1992

Claims (1)

[Claims] In a semiconductor device in which an integrated circuit chip is sealed with resin, the color of the sealing resin is a color that makes it difficult to absorb infrared energy.
A semiconductor device characterized in that an external lead terminal has a color that easily absorbs infrared energy.