| 摘要 |
977,284. Semi-conductor devices. SIEMENSSCHUCKERTWERKE A.G. Dec. 28, 1962 [Dec. 30, 1961], No. 48947/62. Heading H1K. A semi-conductor device comprises a semiconductor body with an electrode having a metal contact face which is held pressed against a second metal contact face of a contact layer on a pressure plate, the two metals being such that they alloy together and the contact faces being substantially plane and at least one being pitted to depths of 0.5 to 50 Á.Fig. 3 shows a PN junction diode comprising a semi-conductor element 5. As a first step a carrier plate 4 of molybdenum is successively covered with an aluminium foil, a P-type silicon wafer, and a gold antimony foil the whole being pressed in graphite powder and heated to 800‹ C. to alloy the portions together. The end faces are lapped with an abrasive to form pitted contact faces and then the semiconductor is etched, washed and oxidized. In the complete assembly, the plate 4 rests on a copper cooling block 2 with a patterned silver foil 7 forming an intermediate layer which provides a sliding contact between elements 4 and 2. The gold-silicon eutectic electrode 6 contacts a pitted silver layer on the lower face of molybdenum disc 10 which is brazed to copper pin 8. A copper ring 9 and steel ring 11 are also provided. A mica disc 12 insulates the upper electrode assembly from three dished springs 14, 15, 16 which are retained by bell-shaped member 17. The outer envelope comprises steel or nickel alloy portions 18 and 20 separated by ceramic portion 19 and copper portion 21 which make pinch connection with pin 8 and an external cable. Fig. 4 shows an alternative arrangement in which the semiconductor element 5 lies between molybdenum disc 4 and silvered molybdenum disc 10a and pressure contacts between pitted surfaces are provided between disc 10a and copper element 8a and between disc 4 and copper base 2a. The edge of the semi-conductor may be covered with a silicone lacquer containing alizarin and resin 23 may fill the free space between discs 4 and 10a. Graphite powder may be used to assist the sliding action in the pressure contacts. The semi-conductor may consist of germanium, silicon, silicon carbide or an A3 B5 or A2 B6 compound and the electrodes may consist of indium or lead arsenic. The arrangement may be applied to diodes, transistors, PNPN devices or photo-electric devices. |
