Improvements relating to semi-conductor devices

摘要

1,140,677. Semi-conductor devices. ASSOCIATED ELECTRICAL INDUSTRIES Ltd. 3 May, 1966 [7 May, 1965], No. 19312/65. Heading H1K. In a semi-conductor device, spring pressure is used to urge the surface of an electrode against the surface of the semi-conductor body and also to urge together abutting parts of a surrounding casing to seal the body within an enclosure. Fig. 1 shows a copper base member 2 carrying a semi-conductor body 1 in contact with the lower surface of a flanged rod 3. Spring washers 4 engage, via washer 7, the edge of a sealing membrane 8 which extends from base 2 and is spun to overlap flange 5; an insulating washer 9 prevents contact between electrode 2 and 3. Thus the spring washers 4 urge abutting surfaces to seal off an enclosure 10 containing the semi-conductor and also provide contact between electrode 3 and semi-conductor body 1. A sealing compound such as grease, and potting resin or rubber may be used to fill cavity 15. The device may be a rectifier or thyristor with the third control electrode positioned in a hollow electrode tube 3. The contact surfaces may comprise gold or silver foils with intervening layers of molybdenum. In a second embodiment, the membrane 8 consists of an annular disc, the inner and outer peripheries of which are urged against portions of the semiconductor body and base 2 respectively, to provide the sealed cavity.