| 摘要 |
724,930. Semi-conductive devices. WESTERN ELECTRIC CO., Inc. Feb. 6, 1953 [Feb. 7, 1952], No. 3401/53. Class 37. [Also in Group XXII] A method of adding to a block of silicon two conductors capable of forming an eutectic with the silicon, one conductor forming a rectifying junction with the silicon, comprises flash heating the assembly of silicon and conductors so that they alloy at the regions of contact. Preferably the silicon is of one conductivity type, and the connecter forming the rectifying region produces a region of the opposite conductivity type in the silicon. As shown, a block of N-type silicon 22 (Fig. 2) is placed on a sheet of gold 23, and an aluminium wire 18 has one end resting on its surface. The assembly is located on a metal filament heater 14 held between clips 13 (Fig. 1) and is flash heated by passing a heavy current through the heater 14 for a short time controlled by timer 21, whereupon the connectors 18, 23 alloy at the regions of contact, the aluminium wire 18 forming a P-type region in the silicon 22. An inert gas is maintained about the assembly by appropriate jets 19. The silicon block 22 is etched before and after treatment, and then dipped in wax to provide a protective coating. In modifications the gold conductor 23 may also be a wire, and both wire conductors 18, 23 may be assembled on the same side of the silicon 22 simultaneously, or on opposite sides by first adding the aluminium wire 18 at a temperature of approximately 650‹ C., and then adding the gold wire 23 at a temperature of approximately 370‹ C. The gold may be mixed with donor impurities, e.g. antimony, arsenic, phosphorus, which do not form an eutectic with silicon, to avoid converting the block to P-type. |
