Properties of Layered Crystals for Radiation Detectors: TlGaSe2 System

摘要

In this paper we report the thermal and electronic characteristics of the ternary compound TlGaSe_2, grown from the melt. The phase-diagram, congruency of material and phase transition were studied by differential thermal analysis. The material melted congruently at 812.9C and did not show any other phases between room temperature and the melting point. Results of crystal growth, and effect of alloying and its effect on crystal growth and properties are also discussed. In high purity material it is easier to cleave the crystal since layers of successive rows of tetrahedrons are turned away from each other by 90°. However, by suitable alloying, the angle of the tetrahedrons can be changed and the tendency to cleave can be decreased. This effect will be evaluated by comparing the microstructural properties of pure and alloyed crystals. By measuring the optical transmission band edge we studied details absorption characteristics to evaluate the effect of impurities on recombination characteristics. Results indicated that there were no donor-acceptor recombinations at or above room temperature.This work was funded by DNDO/DHS, Washington DC.