Ab initio guided optimization of GaTe for radiation detection applications

Article

关键词: TOTAL-ENERGY CALCULATIONS;    MOLECULAR-DYNAMICS;    ANISOTROPY;    COMPOUND;    GROWTH;    GASE;   

DOI  :  10.1103/PhysRevB.84.165206

来源: SCIE

【 摘 要 】

The development of semiconductor-based radiation detectors that display high energy resolution while operating at room temperature is a pressing need for scientific applications as well as homeland security. Practice has proven that the real performance of materials in such applications is often hindered by intrinsic defects and accidental impurities. Experimental efforts to improve the properties of such materials are both time consuming and costly, since they rely largely on trial and error. In this paper, the properties of gallium telluride (GaTe)-a high-Z, moderate-band-gap semiconductor-are investigated for room-temperature radiation detection applications. Systematic theoretical modeling based on density functional theory calculations is used to suggest experimental processes to grow this semiconductor with optimal properties. The goal is to judiciously identify the most detrimental native defects and devise ways to minimize their occurrence as well as compensate their electronic impact on the crystal. The analysis suggests that material grown Ga rich would have significantly higher resistivity, carrier mobilities, and carrier lifetimes compared to Te-rich material. In addition, Ge doping and In doping can be effective for carrier compensation of the material. Doping with Ge can be especially effective, if the ambipolar nature of substitutional incorporation on both Ga and Te sites is exploited.

【 授权许可】

Free