Patent GB-1084817-A (GB)
Title: Process for the monocrystalline deposition of semiconductor compounds
IPC: H01L21/36
Filed: 1964-09-17
Abstract: A process for the monocrystalline deposition of semi-conductor compounds comprising two or three components of which one is two are sparingly volatile and the other is or the others are relatively readily volatile, on a substrate from the gas phase, in a closed or open system, comprises passing a vapour current, comprising one or two readily volatile components of the required compound, whose average vapour pressure is approximately equal to the decomposition vapour pressure of the depositing compound, first over or through a "basic material" which is in the molten state or has a temperature at which the or each less volatile components has such a vapour pressure that it is transported by the current of the more volatile component or components and then over a substrate which may be the same semi-conductor compound or a chemically or electrically different semi-conductor compound are probably in the form of small discs, and which is at 20 DEG -200 DEG  C. below the temperature of the "basic material".  The basic material comprises the or each sparingly volatile component, the semi-conductor compound itself or a mixture of such substances. The vapour current may be produced by sublimation of the more volatile component(s) across the reaction vessel and back again or by continuous thermal circulation of a vapour stream of the more volatile component(s). The vapour current of the more readily volatile component(s) may be derived by volatilization of the components themselves or of a compound thereof. Advantageously the vapour current may be conveyed over the solid or liquid heated other components in the sequence of their decreasing volatility. Simultaneous doping may be effected using components containing selected impurities.  If the "basic material" is used in solid form the vapour current may be conveyed through a large quantity of granular basic material.  The basic material may be varied to produce layers of different chemical composition or electrical properties on the substrate.  Compounds which may be prepared by the method include III/V or II/VI type semi-conductors e.g. boron phosphide, aluminium nitride, aluminium phosphide, aluminium arsenide, gallium phosphide, gallium arsenide, indium nitride, indium phosphide, indium arsenide and the sulphides, selenides and tellurides of zinc, cadmium and mercury.  Also detailed are the compounds AIII1 CV1- y or AIIIx B1- xIII CV1- x e.g. gallium-arsenic phosphide and gallium-indium arsenide, and the sulphides, selenides and tellurides of tin, lead or bismuth.ALSO:A process for the monocrystalline deposition of semi-conductor compounds comprising two or three components of which one is or two are sparingly volatile and the other is or the others are relatively readily volatile, on a substrate from the gas phase, in a closed or open system, comprises passing a vapour current, comprising one or two readily volatile components of the required compound, whose average vapour pressure is approximately equal to the decomposition vapour pressure of the depositing compound, first over or through a "basic material" which is in the molten state or has a temperature at which the or each less volatile components has such a vapour pressure that it is transported by the current of the more volatile component or components and then over a substrate which may be the same semi-conductor compound or a chemically or electrically different semi-conductor compound are probably in the form of small discs, and which is at 20-200 DEG  C. below the temperature of the "basic material."  The basic material comprises the or each sparingly volatile component, the semi-conductor compound itself or a mixture of such substances. The vapour current may be produced by sublimation of the more volatile component(s) across the reaction vessel and back again or by continuous thermal circulation of a vapour stream of the more volatile component(s). The vapour current of the more readily volatile component(s) may be derived by volatilization of the components themselves or of a compound thereof.  Advantageously, the vapour current may be conveyed over the solid or liquid heated other components in the sequence of their decreasing volatility. Simultaneous doping may be effected using components containing selected impurities.  If the "basic material" is used in solid form the vapour current may be conveyed through a large quantity of granular basic material.  The basic material may be varied to produce layers of different chamical composition or electrical properties on the substrate.  III/V or II/VI type semi-conductors, e.g. boron phosphide, aluminium nitride, aluminium phosphide, aluminium arsenide, gallium phosphide, gallium arsenide, indium nitride, indium phosphide, indium arsenide and the sulphides, selenides and tellurides of zinc, cadmium and mercury may be prepared.  Also detailed are the compounds A1IIICV1-y or AxIIIB1-xIIICV1-x, e.g. gallium-arsenic phosphide and gallium-indium arsenide, and the sulphides, selenides and tellurides of tin, lead or bismuth.