| 摘要 |
890,817. Semi-conductor devices. SIEMENS & HALSKE A.G. July 31,1959 [July 31, 1958], No. 26349/59. Class 37. A semi-conductor arrangement comprises a body of a first semi-conducting material and, alloyed thereto, a composite material consisting of both a metal and a second semi-conductor material having an energy gap larger than that of the first material, the melting point of the second semi-conductor material and that of the composite material, being respectively higher and lower than that of the first semi-conductor material. Preferably, the metal has a melting point below that of the second semi-conductor material and also below that of the first material. In a preferred arrangement the metal forms a eutectic mixture with the second material so that even where the melting points of the metal and second material are above, the mixture has a melting point below that of the first material. Germanium and silicon may be the first and second materials respectively and the added metal gallium, indium, gold or tin. When the composite material melts, the metal diffuses into the germanium carrying the silicon with it. Where the added metal has no doping effect a second doping metal, e.g. gallium may be added. It is stated that the arrangement reduces the current carried by the minority carrier from the base into the emitter. In a PNP transistor both the emitter and the collector may be formed of the composite material. |
