| 摘要 |
<p>749,019. Point contact transistors. BRITISH THOMSON-HOUSTON CO., Ltd. Aug. 25, 1954 [Sept. 2, 1953], No. 24273/53. Class 37. An hermetically sealed transistor comprises emitter and collector electrodes 7, 8 mounted on or forming extensions of a pair of leads 2, 3 passing through a metal disc 1 via glass to metal seals 4, 5, the ends of the electrodes being bent over towards the disc to contact a flake 9 of semi-conductor material, e.g. Ge, mounted on a metal base 10 located between the leads and supported from the disc, and a metal cup 12 the rim of which is sealed by welding or soldering to the disc in a region 13 beyond the seals. The base 10 is formed with a plane face adjacent the upstanding arm of L-shaped member 11 the base of which is secured to the disc. After assembly of the electrodes the pressure of the electrodes on the flake is adjusted by adjustment of the vertical position of base 10 by means of a jig. Base 10 is then resistance welded to member 11, its heat capacity preventing a rise of temperature harmful to the flake. The cup 12 is then resistance welded at its flange to a ridge 13 at the edge of the disc, the remoteness of this point from flake 9 preventing harmful rise of temperature thereof. In an alternative arrangement, Fig. 4, the wafer is mounted on the central part of a zig-zag strip 14 to the underside of which base 16 is secured. Adjustment of electrode pressure is made in this case by horizontal movement of the feet 16. The electrodes 7, 8 may be in the form of ribbons cut from sheet material.</p> |
