Electrical translating materials and devices and method of making them

Abstract

Abstract 594,959. Detectors. WESTERN ELECTRIC CO., Inc. Oct. 11, 1944, No. 19628. Convention date, July 28, 1943. [Class 40 (v)] A method of making elements of electrical rectifiers comprises causing a silicon body to react with a lead compound to form a crust on the surface of the silicon, freeing some elemental lead which enters into solution with the silicon and removing the crust to expose a surface of the silicon with which the lead is alloyed. In Figs. 1, 3, a layer of silicon 2 is deposited on a strip of tantalum 1 by heating the strip in an atmosphere of silicon tetrachloride and hydrogen, further heat treatment causing this layer to melt, whereupon it is allowed to cool and crystallize. The strip is mounted on stands 3, 4 in an exhaustion chamber 7 in which is also mounted a metallic trough 6 containing lead oxide, which, after the exhaustion of the chamber, is heated by source 10 through circuit 14. The heated oxide evaporates and forms a layer 15 on top of the silicon layer, and on heating the strip with a current through leads 16, 17, these layers 15, 2 react to form a crust under which is formed a layer of lead and silicon alloy. The crust is then removed, leaving the layer of said alloy and the strip is then ready for utilization. In a crystal rectifier (Fig. 6) a portion of the strip is welded by its tantalum strip to a metal stud 19 threaded into a ceramic cylinder 21, into the other end of which is threaded a hollow stud 22. This stud receives a cylindrical metal contact holder 24, which is adjusted until the tip end of a tungsten wire 25 contacts with the alloy surface of 18, and then locked in this position by setscrews 26.

Inventors

• 👤 Walter H Brattain

Bibliographic Details