METHOD OF OBTAINING A CDTE OR CDZNTE SINGLE CRYSTAL

摘要

Process for obtaining a monocrystal of Cd1-xZnxTe, in which x is 0 - 0.2, by stages in which a polycrystalline block is obtained by sublimation of a block source, then a monocrystal is obtained by re-heating in isothermal conditions under a controlled partial pressure of cadmium and at a controlled temperature. The process is carried out in the stages : (a) obtaining of a source material of Cd1-xZnxTe of a composition approximating to that corresponding to congruent sublimation either by crystallisation from a liquid Cd1-xZnxTe by the horizontal Bridgman technique under a partial pressure of Cd to adjust the stoichiometry, or by re-heating of a material Cd1-xZnxTe pre-synthesized at 800 - 900 degreesC. in a capillary ampoule with extremity at ambient temperature; (b) obtaining of a polycrystalline block of Cd1-xZnxTe by sublimation of a solid source charge in a closed container at a zone temperature in which the source charge is localized at 900 - 1000degreesC, the temperature difference. DELTAT, between the zone of the charge source and the crystal deposition zone being 30 - 50degreesC; (c) obtaining of a monocrystal of Cd1-xZnxTe by recrystallization of the polycrystalline block by re-heating in isothermal conditions under a partial pressure of Cd of 4x10<5> - 6x10<5> Pa and at 1000 - 1060 degreesC for 50 -200 hrs.