COMPARATIVE STUDY OF CDTESE AND CDZNTE SUBSTRATES USING IMPROVED CRYSTAL GROWTH METHODS

SINGLE CRYSTALLINE SUBSTRATES OF CDTESE AND CDZNTE, NOMINALLY LATTICE MATCHED TO HGCDTE (205 CD), WILL BE PREPARED FROM CRYSTALS GROWN BY A NEW PROCESS. THE NEW CRYSTAL GROWTH APPARATUS IS FREE OF QUARTZ AND PROVIDES IMPROVED GROWTH CONDITIONS THROUGH TEMPERATURE PROFILING AND PRESSURE CONTROL METHODS THAT ARE PRECLUDED IN CONVENTIONAL GROWTH SYSTEMS BY HIGH TEMPERATURE AND PRESSURE REQUIREMENTS. IT IS ANTICIPATED THAT SUBSTRATES WITH HIGH PURITY EXCELLENT CRYSTAL MORPHOLOGY AND AREAS GREATER THAN 25 SQ CM WILL BE PRODUCED. CHARACTERIZATION WILL INCLUDE ELECTRON MOBILITY-LIFETIME PROFILING BY ALPHA-PARTICLE EXCITATION, IN ADDITION TO STANDARD MEASUREMENTS. RESULTS OF THE PROGRAM SHOULD 1) ALLOW A CRITICAL COMPARISON TO BE MADE BETWEEN CDTESE AND CDZNTE SUBSTRAGES, 2) PROVIDE SIGNIFICANT NEW INFORMATION RELATED TO LATTICE MATCHING, 3) INCREASING UNDERSTANDING OF THE LATTICE STABILIZING EFFECTS OF ALLOYING, AND 4) DEMONSTRATE THAT IMPROVED QUALITY SUBSTRATES OF CDTE TYPE MATERIALS CAN BE ACHIEVED WITH A NEW CRYSTAL GROWTH METHOD.