| 摘要 |
1337999 Phosphides SONY CORP 11 Dec 1970 [13 Dec 1969 (4)] 59080/70 Heading C1A [Also in Division B1] A phosphide is made by feeding inert gas into a reaction zone containing a phoaphideforming material and a solid or liquid source of gaseous phosphorus, and maintaining the gas at a pressure at least equal to the decomposition pressure of the phosphide; heating the reaction zone sufficiently to vaporize at least a part of the phosphorus source at a pressure about equal to the pressure of the inert gas inside the reaction zone; and heating the phosphideforming material to a temperature sufficient to react with the phosphorus vapour, while simultaneously maintaining an upper part of the reaction zone at a temperature below the inversion temperature of liquid phosphorus to red phosphorus such that an atmosphere of gaseous phosphorus is formed below, and in equilibrium with, an atmosphere of inert gas. In one embodiment (Fig. 3), a hollow watercooled condenser 7 is located above crucible 10 in a quartz reaction chamber 5 provided with inlet 5A for inert gas, and heater 11. In operation, red phosphorus or stable liquid phosphorus 8 is vaporized by heating the reaction chamber to about 430‹ C. The condenser surface 7A is maintained at a temperature above the melting point of yellow phosphorus (44‹ C.) but below the temperature of inversion to red phosphorus (250‹ C.) so that drops of liquefied yellow phosphorus 12 return to the heating zone and an atom atmosphere of yellow phosphorus vapour at constant vapour pressure is established at the same pressure as the inert gas 6. The vapour pressure of the phosphorus can be controlled by changing the pressure of the inert gas. A Group III element, e.g. In, Ga, or a mixture of the element and pre-formed phosphide is placed in crucible 10 in which phosphide synthesis or monocrystalline growth occurs. The condenser 7 is formed of a metal non- reactive to phosphorus e.g. Al or Ti. In further embodiment (not shown) the reaction chamber is open-topped and enclosed in a pressure vessel filled with inert gas, with the condenser in the form of a coil or annular chamber. The crucible may be movable in and out of hot zone provided by an annular graphite heater inside the reaction chamber and surrounding the crucible. Monocrystals, e.g. gallium posphide are made in apparatus in which, e.g. (1) gallium phosphide is precipitated from molten gallium held in a crucible along which a temperature gradient is maintained (see Division B1); (2) a monocrystal, formed on a seed fixed on the end of a rod is pulled from a melt. |
