| 摘要 |
1,238,710. Semi-conductor devices. ALLMANNA SVENSKA ELEKTRISKA A.B. 26 Nov., 1968 [27 Nov., 1967], No. 55958/68. Heading H1K. [Also in Division C7] A solder suitable for use in soldering current terminals on to a semi-conductor wafer 11 consists of a eutectic alloy of gold and thallium, or of an alloy having gold and thallium as the main constituents and a melting point which does not differ by more than 50‹ C. from the melting point of 131‹ C. of the eutectic alloy of 73% by weight of thallium and 27% by weight of gold. The surfaces of the semi-conductor wafer are provided with electrodes 12, 13 of gold or a gold alloy such as gold-silicon-antimony or goldsilicon-boron before soldering, and are then bonded to bolt 14 and counter electrode 15, of copper, copper alloy, silver or silver alloy, serving as the current terminals, by layers 16 and 17 of the solder. A heat sink 32 and casing are provided. Embodiments showing other forms of heat sink and casing arrangements for diodes, transistors and thyristors are described, in some of which support plates of molybdenum and tungsten covered with gold or gold alloy on the solder-facing side may be present. |
