Characterization and analyses of the crystallization quality and properties of ACRT-VBM Hg_1-xMn_xTe crystals

Hg_1-xMn_xTe crystals of various diameters (5 mm and 15 mm respectively), grown by vertical bridgman method with accelerated crucible rotation technique (ACRT-VBM), were etched to assess the macroscopic and microscopic crystallization quality. Dislocations, Te-rich inclusions, grain boundary, and impurities were found and measured. In order to improve the electronic properties of the samples which are dominated by defects, slices of Hg_1-xMn_xTe crystals were annealed under low temperature (210-250°C). The electronic properties were evaluated by Hall measurement. Experimental results show that the conductivity type can be converted by annealing and the crystal defects, such as dislocation density and distribution, Te-rich inclusions and grain boundary could affect the electrical properties.