Type conversion of polycrystalline CdZnTe thick films by multiple compensation

摘要

The multiple compensated polycrystalline CdZnTe thick films have been deposited by thermal evaporation method. The heavy metals of Pb and Sn have been co-doped with Cl in order to fully compensate Cd vacancies in polycrystalline CdZnTe films due to the limited solubility of Cl in CdZnTe. The drastic variations of the resistivity and conduction type in the CdZnTe films were observed by doping with heavy metals. The intensity of A-center levels, which are normally found in a compensated single CdZnTe crystal, was decreased along with the increase of resistivity in polycrystalline CdZnTe samples. The electron mobility is about 88 cm~2/Vs, and a well resolved gamma ray spectrum of ~(241)Am has been observed for these polycrystalline CdZnTe thick films for the first time.