| 摘要 |
848,039. Semi-conductor devices. WESTINGHOUSE ELECTRIC CORPORATION. May 2, 1958 [May 9, 1957], No. 14048/58. Class 37 A semi-conductor silicon diode comprises a base contact member consisting of tungsten or tantalum or an alloy thereof having a co-efficient of thermal expansion approaching that of silicon on a relatively thin coating of gold, platinum or rhodium from 1 mil to 0À01 mil thick bonded to this base contact member to facilitate soldering to a base mount. Fig. 1 shows a silicon wafer 20, a base contact member 12 consisting of tunsten, tantalum or alloys thereof with osmium, platinum, nickel, cobalt, silicon or silver, a coating 16 of gold, platinum or rhodium, a silver base solder consisting of an alloy of two or more metals from the group silver, tin, germanium, lead, antimony and silicon, and a layer of aluminium or aluminium base alloy 22 attached to lead 28, this aluminium alloy being of aluminium with magnesium, zinc, gallium, indium and, or germanium. These components are assembled as shown and heated to about 1000‹C. in vacuo in order to fuse the various layers together. The base contact member is then soldered to the base mount by means of a low melting point solder 36 which melts below 300 ‹C. In an alternative embodiment (Fig. 2 not shown) the layer of gold, platinum or rhodium completely encloses the base contact member. The device is then etched in a mixture of hydrofluoric and nitric acids and then hermetically sealed. |
