JPS61288577A - Semiconductor solid-state image pickup device - Google Patents

Abstract

PURPOSE:To improve the yield of optical selection of the device and to reduce the cost by overlapping a transparent cap to a case mounted on a semiconductor chip, providing an adhesives layer so as to be bridged over the case and the transparent cap and providing a frame onto the adhesives. CONSTITUTION:The case 1 is made of anlumina ceramic used for a conventional semiconductor device case, provided with a step having a cap 2, the cap 2 is made of a transparent glass and a semiconductor device sealing low melting point glass is used for the sealing adhesives 3. The frame 4 is formed by press- forming to powder alumina and baking it and then the sealing adhesives 3 is provided to one face of the frame 4 by 100-300mum thick by the screen printing. The semiconductor solid-state image pickup device is sealed airtightly by setting the cap 2 to the case 1, assembing the frame 4 so that the sealing adhesives 3 is bridged over the case 1 and the cap 2 and heating the frame 4 while applying a weight to it.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a sealing structure for a semiconductor solid-state imaging device.

[Conventional technology]

Conventionally, a semiconductor solid-state imaging device using a sealing adhesive has a structure in which the sealing adhesive is sandwiched between the bonding surfaces of a cap and a case, as shown in FIG.

The sealing method is to apply a sealing adhesive, such as low-melting glass, on the sealing surface of the cap in advance by screen printing, etc., and after combining it with the case, heat it under the sealing conditions of the sealing adhesive. There is a way to do it.

[Problem that the invention seeks to solve]

The sealing method using the conventional sealing structure described above has the following drawbacks.

Since the sealing adhesive is provided around one side of the cap, when screen printing the paste sealing adhesive, droplets of the sealing adhesive often adhere to the lighting area of the cap. After being sealed, it may cast a shadow on the photosensor, resulting in a defective imaging device. Therefore, it becomes necessary to sort the caps after screen printing, which significantly reduces the manufacturing yield of the caps and increases costs.

Furthermore, it is difficult to completely screen out adhesives that adhere to sealing adhesives with a diameter of approximately 10 μm, which is one of the causes of defects during optical screening after assembly of semiconductor solid-state imaging devices. ing.

Therefore, a method was devised in which only the sealing adhesive was formed into a frame shape, combined with the cap and case, and then heated under the conditions for sealing the sealing adhesive. With this method, droplets of sealing adhesive will not adhere to the lighting part of the cap, but the low melting point glass frame is mechanically fragile, resulting in low manufacturing yields and high costs. , it becomes very difficult to handle after molding.

[Means for solving problems]

In the semiconductor solid-state imaging device according to the present invention, a light-transmitting cap is placed over a case to which a semiconductor chip is attached, and an adhesive layer is provided so as to span over the case and the light-transmitting cap. It has a frame above it.

〔Example〕

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a longitudinal sectional view of an embodiment of the present invention.

The case 1 is made of alumina ceramics, which is commonly used in cases for semiconductor devices, and is provided with a step into which the cap 2 is fitted. The cap 2 is made of translucent glass. The sealing adhesive 3 is a low-melting glass for sealing semiconductor devices, but the sealing temperature is particularly within a range where the sealing temperature does not adversely affect other components, such as the semiconductor solid-state image sensor, case, cap, etc. It is necessary that the Alternatively, a resin adhesive may be used. The frame 4 was made by press-molding powdered alumina and then firing it. Next, apply the sealing adhesive 3 by screen printing to one side of the frame 4 to a thickness of 100 mm.
A thickness of about 300 μm was provided.

In general, the material for the frame 4 has a thermal expansion coefficient that can withstand the sealing temperature, has mechanical strength that will not damage it under normal operation, will bond with the sealing adhesive, and will not cause the bond to break due to temperature cycling. Anything that has . For example, Fe-Ni
It may also be a metal such as an alloy.

In this embodiment, the dimensions of the frame 4 are the thickness Q, 5n+, and the inner and outer dimensions are such that it spans the case 1 and the cap 2, and the seal path on the case 1 side is calculated to be an average of 1. Qtll.

The seal path on the cap 2 side was calculated to be 0.5111 on average.

If it is necessary to increase the adhesive strength between case 1 and cap 2, increase the contact area with the sealing adhesive.

A taper may be provided on the sealing surfaces of the case 1 and the cap 2 in order to increase the resistance.

To seal the semiconductor solid-state imaging device, after fitting the cap 2 into the case 1 and assembling the frame 4 so that the sealing adhesive 3 spans the case 1 and the cap 2, approximately 10 g of sealing adhesive 3 is applied to the frame 4.
The tube was heated at 450±10.degree. C. for 15 minutes while applying a load of 1.5 mm/m'' to perform airtight sealing.

〔Effect of the invention〕

As explained above, according to the present invention, by providing a structure in which an adhesive layer is provided so as to span over the case and cap of a semiconductor solid-state imaging device, it is possible to handle a frame with a sealing adhesive attached. , workability during sealing work can be improved. Furthermore, since the sealing adhesive is not splashed, the production yield of the cap is not affected, which has the effect of improving the optical sorting yield of semiconductor solid-state imaging devices and reducing costs.

[Brief explanation of drawings]

The first reason is a vertical cross-sectional view of an embodiment of the present invention, and FIG. 2 is a cross-sectional view of a conventional semiconductor solid-state imaging device. 1...Case, 2...Cap, 3.
...Sealing adhesive, 4...Frame, 5...
...Semiconductor solid-state image sensor.

Claims (1)

[Claims] 1. In a semiconductor solid-state imaging device having a structure in which a semiconductor solid-state imaging device is mounted on a case, a translucent cap is placed over the case, and an adhesive is applied so as to straddle the case and the translucent cap. 1. A semiconductor solid-state imaging device characterized by having a structure in which a layer is provided and a frame is provided on the adhesive layer. 2. The semiconductor solid-state imaging device according to claim 1, wherein the frame is made of alumina ceramic.