Abstract Thallium bromide (TlBr) is an attractive semiconductor material for fabrication of radiation detectors due to its high photon stopping power originating from its high atomic number, wide band gap and high resistivity. In this paper the vertical Bridgman method was used for crystal growth and TlBr single crystals with diameter of 15 mm were grown. X-ray diffraction (XRD) was used to identify phase and orientation. Electron backscatter diffraction (EBSD) was used to investigate crystal microstructure and crystallographic orientation. The optical and electric performance of the crystal was characterized by infrared (IR) transmittance spectra and I-V measurement. The types of point defects in the crystals were investigated by thermally stimulated current (TSC) spectra and positron annihilation spectroscopy (PAS). Four types of defects, with ionization energy of each defect fitting as follows: 0.1308, 0.1540, 0.3822 and 0.538 eV, were confirmed from the TSC result. The PAS result showed that there were Tl vacancies in the crystal.

中文翻译：

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大尺寸 TlBr 单晶生长和缺陷研究

摘要 溴化铊 (TlBr) 因其高原子序数、宽带隙和高电阻率而具有高光子阻止能力，是一种用于制造辐射探测器的有吸引力的半导体材料。本文采用垂直布里奇曼法进行晶体生长，生长直径为 15 mm 的 TlBr 单晶。X 射线衍射 (XRD) 用于鉴定相和取向。电子背散射衍射 (EBSD) 用于研究晶体微观结构和晶体取向。通过红外（IR）透射光谱和IV测量表征晶体的光学和电学性能。通过热激电流 (TSC) 光谱和正电子湮没光谱 (PAS) 研究了晶体中点缺陷的类型。四种缺陷，与每个缺陷拟合的电离能如下：0.1308、0.1540、0.3822 和 0.538 eV，由 TSC 结果证实。PAS结果表明晶体中存在Tl空位。