Electrical and Optical Properties of Indium and Lead Co-Doped Cd_0.9Zn_0.1Te

We have investigated the electrical and optical properties of Cd_0.9Zn_0.1Te:(In,Pb) wafers obtained from the tip, middle, and tail of the same ingot grown by modified vertical Bridgman method using I-V measurement, Hall measurement, IR Transmittance, IR Microscopy and Photoluminescence (PL) spectroscopy. I-V results show that the resistivity of the tip, middle, and tail wafers are 1.8 × 10¹⁰, 1.21 × 10^9, and 1.2 × 10¹⁰ Ω·cm, respectively, reflecting native deep level defects dominating in tip and tail wafers for high resistivity compared to the middle part. Hall measurement shows the conductivity type changes from n at the tip to p at the tail in the growth direction. IR Transmittance for tail, middle, and tip is about 58.3%, 55.5%, and 54.1%, respectively. IR microscopy shows the density of Te/inclusions at tip, middle, and tail are 1 × 10³, 6 × 10² and 15 × 10³/cm² respectively. Photoluminescence (PL) spectra reflect that neutral acceptor exciton (A⁰,X) and neutral donor exciton (D⁰,X) of tip and tail wafers have high intensity corresponding to their high resistivity compared to the middle wafer, which has resistivity a little lower. These types of materials have a large number of applications in radiation detection.