JPS5949697B2 - semiconductor equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a semiconductor device, particularly a packaged semiconductor device.

A conventional semiconductor device of this type will be described with reference to FIG.

That is, the package base 1 is made of a single piece such as ceramic, and a semiconductor element 2 is mounted on the package base 1. In order to protect the semiconductor element 2 from the atmosphere, an element space 4 is provided around it. The element space 4 is hermetically sealed by sealing the lid 3 with a sealing material 5. In this case, the sealing material 5 is made of metal such as solder, inorganic material such as glass or ceramic, or organic material such as resin.
They are selected and used depending on the quality and cost required for each. In the semiconductor device with the above structure,
When the sealing material is made of metal, it is possible to maintain a relatively high airtightness, but not only does it require metallization and a special high-temperature furnace for sealing, but the material itself is expensive and gradually leaks into the outside air. There was a risk that the moisture would diffuse and penetrate, leading to deterioration of device characteristics. In addition, inorganic and organic materials are inexpensive and can be easily sealed, and resin seals in particular have the advantage of not requiring heating, but they generally have disadvantages such as poor airtightness and cannot be applied to highly reliable products. It was hot. In view of these conventional circumstances, the present invention aims to improve reliability by protecting a semiconductor element with a double sealed space inside and outside, and by reducing the pressure difference between the inside and outside to zero or positive pressure. The purpose is to provide a semiconductor device that is easy and inexpensive.

Hereinafter, embodiments of the apparatus according to the present invention will be described in detail with reference to FIG.

FIG. 2 is a sectional view showing one embodiment of the present invention, and in this figure, the same parts as in FIG. 1 are designated by the same reference numerals.

In this embodiment, after a semiconductor element 2 is mounted on a package base 1 in the same manner as in the conventional example, this semiconductor element 2 is
An inner cover 6 is applied leaving an element space 4 inside so as to enclose the elements, and the inner cover 6 is fixed to the package base 1 with an inner sealing material □. Then, an outer cover 8 is applied leaving an insulating space 10 between them so as to enclose the inner cover 6, and the outer cover 8 is attached to the package base 1 using an external sealing material 9.
By fixing the semiconductor element 2 to the air, the semiconductor element 2 is doubly hermetically sealed from the atmosphere by the first element space 4 and the second insulating space 10. In this case, the internal sealing material 7 and the external sealing material 9 are made of materials having different solidification temperatures. Here, by setting the temperature at which the outer cover 8 is sealed a little higher than the temperature at which the inner cover 6 is sealed, the pressure of the gas remaining sealed in the insulating space 10 can be lowered than in the element space 4. , gas intrusion into the element space 4 due to pressure difference is prevented.

Further, even when materials having the same solidification temperature are used for the internal sealing material 7 and the external sealing material 9, the pressure difference between the element space 4 and the insulating space 10 can be eliminated.

Therefore, in the semiconductor device of the above embodiment, the semiconductor element 2 is hermetically sealed by the double space of the first element space 4 and the second insulating space 10 formed by the inner cover 6 and the outer cover 8, Furthermore, since the element space 4 is maintained at a more positive or equal pressure than the insulating space 10, the rate of infiltration of impurity gases such as water vapor from the atmosphere into the element space 4 can be significantly reduced. Even if a resin material is used for the sealants 7 and 9, the semiconductor element 2 can be sufficiently protected.

As detailed above, according to the present invention, a semiconductor element can be protected from the atmosphere with an extremely simple configuration, and a highly reliable, easy and inexpensive semiconductor device can be provided. effective.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an example of a conventional package type semiconductor device, and FIG. 2 is a sectional view showing an embodiment of the semiconductor device according to the present invention. DESCRIPTION OF SYMBOLS 1...Package base, 2...Semiconductor element, 4...Element space, 6...Inner lid,
7... Internal sealing material, 8... Outer lid, 9
...External sealing material, 10...Insulating space.

Claims (1)

[Claims] 1. On a package base in which a semiconductor element is provided, a first element space is formed, which is hermetically sealed by applying an inner lid so as to surround the semiconductor element, and a first element space is hermetically sealed by applying an outer lid to surround the inner lid. The semiconductor element is doubly hermetically sealed by a second hermetically sealed insulating space, and the solidification temperature of the internal sealing material that hermetically seals the inner lid is controlled by the solidifying temperature of the internal sealing material that hermetically seals the outer lid. A semiconductor device characterized by having a solidification temperature lower than or equal to the solidification temperature of a sealing material.