Abstract: A method for producing a large high-quality single crystal of Cadmium-Indium-Telluride is disclosed wherein a stoichiometric crystal is produced from a non-stoichiometric melt composition. An initial melt composition corresponding to approximately 62 mole % to 90 mole % In.sub.2 Te.sub.3 and 38 mole % to 10 mole % CdTe, respectively, is prepared and sealed in an evacuated ampoule and then heated to completely melt the mixture. Growth of a single crystal of CdIn.sub.2 Te.sub.4 is initiated and maintained from the non-stoichiometric melt mixture by lowering the melt through its corresponding phase-equilibrium melting point. Upon cooling to room temperature, the large single crystal so produced is removed from the ampoule.

Abstract: Desired conductivity type and carrier concentration in the Group II-VI, III-V, and IV-VI compounds in which at least one constituent is volatile is obtained by varying the partial pressure of one of the volatile constituents with respect to the compound solid, which is then controllably cooled while simultaneously changing the component pressure to maintain the compound within the high resistivity area of its phase diagram. For example, donor doped cadmium telluride is maintained at a temperature range of about 1000.degree. C. at 0.9 atmospheres in the constituent atmosphere to obtain high resistivity (up to 10.sup.9 ohm-cm.) and then slow-cooled to a preferred temperature of 700.degree. C. or lower in the high resistivity region and/or between the stoichiometric line and its dope line, and then into the high resistivity region but above its minimum pressure line where the compound begins to sublime congruently, followed by removal of the material from the furnace.