| 摘要 |
1,116,363. Semiconductor devices. SIEMENS-SCHUCKERTWERKE A.G. 13 Sept., 1965 [12 Sept., 1964], No. 39066/65. Heading H1K. A semi-conductor device having two electrodes on one major face arranged so that one electrode lies within an aperture in the second electrode, is contacted by two metallic members, the contact face of one of the members contacting substantially the whole of the free surface of the second electrode and extending over the edge of the aperture. Fig. 4 shows part of an S.C.R. provided with an annular control electrode 5. The contact member 20 which is pressed into electrode 5 is also annular and extends over the inside edge of the electrode to increase the current carrying capability and cooling effect of the contact. The edge of member 20 is rounded to prevent the generation of high electric fields. Contact member 28 may also extend over the outside edge of electrode 7. The production of an S.C.R., Fig. 2 (not shown), is described and comprises diffusing aluminium, gallium, or boron into the surface of an N-type silicon wafer, forming a ring-shaped groove or removing the edge of the wafer by grinding, etching, or sandblasting to form three layers (2, 3, 4), alloying an annular foil (5) of gold containing antimony and a disc (7) of gold containing boron to the upper surface to form emitter region (6) and an ohmic contact to layer (4) respectively, and alloying a molybdenum or tungsten carrier plate to layer (3) using a foil (8) of gold containing boron. The use of aluminium foils is also mentioned. The device may be encapsulated. |
