| 摘要 |
<PICT:1102205/C1/1> An epitaxially-grown layer of a high-purity binary semi-conductor compound, an AIII BV compound of stoichiometric composition, is prepared in an apparatus as shown in Fig. 1 by heating in a reaction vessel 1, preferably of quartz, one component of the semi-conductor compound, such as gallium or indium, to a temperature above its melting point but not substantially above 400 DEG C., whilst the second component is added to the melt. This second compound 5 may be phosphorous trichloride or arsenic trichloride and is added to the melt from a dropper-funnel 6. The reaction is carried out in the absence of moisture using a shielding gas such as hydrogen, nitrogen or a rare gas. The powdered semi-conductor compound thus formed is extracted from the reaction products and subjected at least once to a transport reaction in which the compound is reacted with a reaction gas such as water vapour and either hydrogen or a halogen or hydrogen halide. This reaction is carried out in a vessel which is heated to a temperature of the order of 3000 DEG C. in the presence of hydrogen or the reaction gas prior to the introduction into this vessel of the powdered semi-conductor compound. After the vessel has been heated and allowed to cool, the powdered semi-conductor compound is introduced and heated in the presence of the reaction gas to a temperature of 800-1000 DEG C., whereby it is transported to a carrier crystal located at a predetermined distance from the semi-conductor and allowed to grow epitaxially on this crystal. This reaction vessel may be of several parts and is constructed wholly of carbon.
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