Patent GB-991184-A (GB)
Title: Apparatus for the production of pure silicon or germanium
IPC: C23C16/44
Filed: 1962-01-26
Abstract: An apparatus for the production of <PICT:0991184/C1/1> silicon by pyrolytic decomposition of a gaseous compound of silicon, comprises a housing having a mouth, base-plate and a heat screening plate together with means for delivery and withdrawing the reactants and gaseous products, and electrical connections to holders to take a resistive means, wherein the heat screening plate bears against the whole surface of the base-plate which faces inwardly of the housing and is mounted either between the base-plate and the housing mouth but wholly externally of the housing or at least partially within the housing and is of the same diameter and shape as the inner wall of the housing. In the Figure, a quartz bell 17 is mounted on a polished plane metal plate 1, e.g. silver, being attached thereto by a flange 17a  and insulating material 18, e.g. polytetrafluoroethylene. Through the plate is introduced a gaseous compound of the material admixed with H2, e.g. SiH4, SiH3Cl, SiH2Cl2, SiHCl3.SiCl4, by pipe 21 whilst the exhaust gases are withdrawn through 16d and 16e.  A bushing 5 which has a cylindrical or conical fit into plate 1, is insulated from the plate by a sleeve of polytetrafluoroethylene 4. Both the plate 1 and the electrical bushing 5 may be cooled.  The electrical connections to the apparatus are made by bus-bars 8 and 26.  The deposition bodies 19 and 20 which are heated as electrical resistance conductors, and made of silicon, are connected by a cone and socket joints, to a bridge 24 made of graphite.  The other ends of the deposition bodies are connected, e.g. by cone and socket joints to supports 12 and 15 which may be of carbon or graphite, which supports are fitted into the base-plate 1 and bushing 5 by e.g. cone and socket joints.  An auxiliary plate 16, e.g. of quartz, which functions as a heat insulating plate to maintain and regulate the temperature in space 22, and having holes 16a -16e of appropriate dimensions for the services &c. passing into space 22, rests upon the plane surface of 1.  The temperature of space 22 may also be regulated by a cooling coil 2 and a heat-sensitive control 27.ALSO:An apparatus for the production of germanium by pyrolytic decomposition of a gaseous compound of germanium, comprises a housing having a mouth, base plate and a heat screening plate together with means for delivery and withdrawing the reactants and gaseous products, and electrical connections to holders to take a resistive means, wherein the heat screening plate bears against the whole surface of the base plate which faces inwardly of the housing and is mounted either between the base plate and the housing mouth wholly externally of the housing or at least partially within the housing inner wall of the housing.  In the figure, a quartz bell 17 is mounted on a polished plane metal plate 1 e.g. silver, being attached thereto by a flange 17a and insulating material 18 e.g. polytetrafluoroethylene.  Through the plate is introduced a gaseous compound of the material admixed with H2 by pipe 21 whilst the exhaust gases are withdrawn through 16d and 16e.  A bushing 5 which has a cylindrical or conical fit into plate 1, is insulated from the plate by a <PICT:0991184/C6-C7/1> sleeve of polytetrafluoroethylene 4.  Both the plate 1 and the electrical bushing 5 may be cooled.  The electrical connections to the apparatus are made by bus-bars 8 and 26.  The deposition bodies 19 and 20 which are heated as electrical resistance conductors, are connected by a cone and socket joints, to a bridge 24 made of graphite.  The other ends of the deposition bodies are connected e.g. by cone and socket joints to supports 12 and 15 which may be of carbon or graphite, which supports are fitted into the base plate 1 and bushing 5 by e.g. cone and socket joints.  An auxiliary plate 16 e.g. of quartz, which functions as a heat insulating plate to maintain and regulate the temperature in space 22, and having holes 16 a-e of appropriate dimensions for the services &c. passing into space 22, rests upon the plane surface of 1.  The temperature of space 22 may also be regulated by a cooling coil 2 and a heat sensitive control 27.