Patent GB-1017249-A (GB)
Title: Improvements in or relating to the deposition of semi-conductor materials
IPC: H01L21/00
Filed: 1963-11-13
Abstract: In coating germanium on to a germanium or other carrier, by the decomposition of a gaseous germanium compound, germanium in powder or massive form rests on a heatable base, and is surrounded by a spacing ring which supports the carrier, and the space between the germanium and the carrier is in free gas exchange with the atmosphere surrounding the spacing ring and the carrier.  A gas which reacts with the germanium at elevated temperature and converts it into a gaseous material is introduced and the gas produced decomposes at the surface of the carrier and deposits thereon a layer of germanium. The carrier may be any semiconductor material, e.g. silicon, silicon carbide, AIII BV or AII BVI compounds, and is preferably monocrystalline, and the powdered germanium may be used in the form of a presintered tablet, or the germanium may be in the form of a monocrystalline disc.  The spacing ring which is inert under the conditions of the reaction e.g. quartz sintered corundum, silicon carbide, carbon, or carbon coated with silicon carbide, may be lapped on both annular faces, and may be provided with at least two annular grooves (see Figs. 3 and 4, not shown) to ensure the desired free gas interchange.  Alternatively, the spacing ring may be oval in shape and the carrier circular (Figs. 5 and 6, not shown) again ensuring the free passage of gases.  The process may be carried out at reduced or atmospheric pressure, or the heating of the base may be initiated at reduced pressure and the deposition carried out at atmospheric pressure.  The reaction gas utilized may be a halogen or a hydrogen halide either alone or mixed with hydrogen or an inert gas.ALSO:In the deposition of semi-conductor material (viz. Ge, Si, SiC, AIIIBV and AIIBVI compounds) by the decomposition of a gaseous compound or gaseous compounds on a carrier, the semi-conductor material in powder or massive form rests on a heatable base, is surrounded by a spacing ring which supports the carrier, and the space between the semi-conductor material and the carrier is in free gas exchange with the atmosphere surrounding the spacing ring and the carrier.  A gas which reacts at elevated temperature with the semi-conductor material and converts it into a gas or mixture of gases is introduced and the gas, or gaseous mixture produced decomposes at the surface of the carrier and deposits thereon a layer of semi-conductor material.  The carrier which is itself a semi-conductor material is preferably monocrystalline and the powdered semi-conductor material used in the process is preferably in the form of a presintered tablet, or the material may be in the form of a monocrystalline disc. The spacing ring which is made of a material inert under the conditions of the reaction, e.g. quartz, sintered corundum silicon carbide, carbon or carbon coated with SiC, may be lapped on both annular faces, and may be provided with at least two radial grooves (Figs. 3 and 4, not shown) to ensure the desired free gas interchange. Alternatively, the spacing ring may be oval in shape and the carrier circular (Figs. 5 and 6, not shown), again ensuring the free passage of gases.  The process may be carried out at reduced or atmospheric pressure, or the heating of the base may be initiated at reduced pressure and the deposition carried out at atmospheric pressure.  A doping substance may be present in the reaction gas or in the semi-conductor material initially converted into the gaseous form.  The reaction gas utilized may be a halogen or a hydrogen halide, or a halide of a metallic or non-metallic element either alone or admixed with hydrogen or an inert gas.