JPH0243732A - Manufacture of semiconductor device - Google Patents

Abstract

PURPOSE:To apply a JCR on the surface of a part, at which a P-N junction is exposed, of a semiconductor substrate in a uniform thickness and to obtain a semiconductor device having high electrical characteristics and a high reliability by a method wherein when the JCR is applied, frame bodies, which each come into contact to the side surfaces of the substrate and whose heights are higher than that of the substrate surface, are provided. CONSTITUTION:When a junction covering resin(JCR) 5 to cover a P-N junction exposed on the surface on the side opposite to the surface, which is fixed on a supporting plate 2, of a semiconductor substrate 1 fixed on the supporting plate 2 is applied on the surface on the side opposite, frame bodies 6, which each come into contact to the side surfaces of the substrate 1 and whose heights are higher than that of the surface of the substrate 1, are provided. For example, after a lead frame mounting part 2 and a connecting lead 4 are each fixed on both surfaces of a planar Si chip 1 with a solder 3, frame bodies 6 to come into contact to the side surfaces of the chip 1 are mounted. The frame bodies 6 may be ready-fixed on a lead frame before being soldered to the chip 1. After that, a JCR 5 is applied on the surface of the chip 1. The material of the frame bodies can be an insulator of ceramic, plastic and so on or any metal.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a method in which the exposed PN junction portion of the surface of a semiconductor substrate fixed on a support plate is protected by applying a bond coating resin (hereinafter referred to as JCR). The present invention relates to a method for manufacturing a semiconductor device.

[Conventional technology]

In order to prevent the characteristics of a semiconductor device using a PN junction from deteriorating, a puff-sealing method is necessary to protect the exposed portion of the PN-junction on the semiconductor substrate surface and its vicinity from the influence of the external atmosphere. As a method of applying polyimide resin or the like to the surface of the semiconductor element, a method is used. FIG. 2 shows an example of such a semiconductor device, in which a silicon chip 1 is soldered onto a mount portion 2 of a lead frame using a solder 3. As shown in FIG. The head 41 of the connection lead 4 is also soldered to the top surface of the chip 1. If the Si chip is planar and the PN junction is exposed on the top surface, JCR5 is placed on the top surface.
Apply.

[Problem to be solved by the invention]

When JCR5 is applied to the top surface of the Si chip 1 as shown in Figure 2, the JCR flows out to the side of the chip as shown in the figure, so the JCR5 around the top surface becomes thinner and there is a drawback that the JCR is not applied uniformly. Ta. As a result, the JCR5 on the exposed part of the PN junction is thin and cannot provide sufficient protection, and the JCR with uneven thickness causes uneven stress on the S.
In addition to the i-chip 1, the electrical characteristics and reliability of the semiconductor device 1 were adversely affected.

The object of the present invention is to eliminate the above-mentioned drawbacks and to
The object of the present invention is to provide a semiconductor device in which a JCR is coated to a uniform thickness on the surface of an exposed N-junction, and has high electrical characteristics and reliability.

[Means to solve the problem]

In order to solve the above problems, the present invention provides a method for applying JCR to cover the PN junction exposed on the surface of a semiconductor substrate fixed on a support plate, on the opposite side to the surface fixed to the support plate. , a frame body that is in contact with the side surface of the semiconductor substrate and whose height is higher than the surface of the substrate.

[Effect]

The frame body in contact with the side surface of the semiconductor substrate prevents the JCR applied to the substrate surface from flowing out to the side surface, so that the JCR can be applied thickly and uniformly to the periphery of the substrate.

〔Example〕

FIG. 1 shows an embodiment of the present invention, and parts common to those in FIG. 2 are given the same reference numerals.

In this embodiment, a lead frame mount portion 2 and connection leads are fixed to both sides of a brainer-type Si chip 1 with solder 3, and then a frame body 6 that contacts the side surface of the Si chip 1 is attached. However, the frame body 6 may be fixed to the lead frame before soldering the chip l.
Apply JCR5 to the surface of the Si chip l. The JCR expands to the inner circumference of the frame 6 and is stopped there, so the JCR
The thickness of the silicon chip 5 is uniform up to the periphery of the Si chip 1, and can be set to any desired thickness. If the frame is to be soldered to the Si chip 1 and the support plate 2 later, the material of the frame may be ceramic, plastic, or other insulating material, or metal. It is necessary to make it from a material with a coefficient of thermal expansion similar to that of the support plate 2 so that thermal stress does not occur due to temperature. The frame 6 may be left in place after applying the JCR, but if it needs to be removed, it may be removed using a material that does not have good wettability with the JCR.
For example, it is easier to remove if it is made of ceramic.

FIG. 3 shows another embodiment, in which the Si chip 1 is fitted into the mount part 2 of the lead frame, and four parts 7 are formed which are deeper than the sum of the thicknesses of the 31,000 knobs 1 and the solder 3 on one side.
After soldering the chip 1 into this recess 7,
If R5 is applied, the mount portion 2 of the lead frame also functions as a frame, and uniform application of JCR similar to the embodiment shown in FIG. 7 is possible. This embodiment can be easily implemented by simply changing the shape of the lead frame, and the step of attaching the frame can be omitted.

〔Effect of the invention〕

According to the present invention, since the JCR coated on the surface of the semiconductor substrate fixed on the support plate is prevented from flowing out to the side surface of the substrate by the frame that is in contact with the side surface of the substrate, a uniform and arbitrary thickness can be applied on the surface. It becomes possible to apply JCR. As a result, the stress applied to the semiconductor substrate by the JCR becomes uniform, and a semiconductor device with improved electrical characteristics and reliability can be obtained.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view of one embodiment of the present invention after applying JCR, Fig. 2 is a cross-sectional view of a conventional JCR fabric after being applied, and Fig. 3 is a cross-sectional view of a different embodiment of the present invention after applying JCRI. . 1: Si chip, 2: Lead frame mount section, 1st
Figure 2 Figure 3

Claims (1)

[Claims] 1) When applying a bonding coating resin to cover the PN junction exposed on that surface to the surface of the semiconductor substrate fixed on the support plate opposite to the surface fixed to the support plate, contacting the side surface of the semiconductor substrate,
A method for manufacturing a semiconductor device, comprising a frame whose height is higher than the surface of a substrate.