Определение параметров системы носителей заряда в Pb1-XSnxTe на основе совместного анализа температурных зависимостей четырех кинетических коэффициентов

Abstract

Experimental studies of transport phenomena in Pb1-xSnxTe provide the most complete information on the kinetics and energy spectrum of charge carriers over a wide range of charge carrier concentration, impurities, and temperature. Significant interest in studying the properties of narrow-gap semiconductors, particularly lead telluridetin telluride single crystals, is attributed to wide possibilities of their practical use as detectors and radiation sources in the infrared spectrum, thermocouples, strain gauges, etc. At the same time, scientific interest in these materials is primarily associated with their unusual galvanomagnetic, thermomagnetic, and magneto-optical properties.The quality requirements for the samples under study are very high in order to obtain reliable experimental results: the volume distribution of the components must be uniform, and mechanical defects must be reduced to minimum. The most effective technique for preparing homogeneous Pb1-xSnxTe single crystals is the gas-phase growth method. We have developed a special technology for gas-phase growth of single crystals using high-purity Pb, Sn, and Te of the OSCh-0000 grade as initial materials (Te was purified by multiple zone recrystallization). Microstructural and spectral studies and Hall-effect measurements have confirmed the high quality of the prepared Pb1-xSnxTe (x = 0.18) single crystals. In this study, the temperature dependences of the thermopower and Nernst- Ettingshausen coefficient of five Pb0.82Sn0.18Te samples at different carrier concentrations (0.52 – 10 17 to 15 – 10 17 cm-3) have been examined.