CdZnTe Energy Levels Induced by Doping of Indium

Photoluminescence (PL) and infrared transmission spectra are used to characterize the In-doped Cd_0.9Zn_0.1Te (CdZnTe:In). The PL spectrum reveals that there are two other strong emissions situated at 1.54 eV and 1.62 eV except the near band edge emission. This indicates that the doped In can lead to two donor levels of 0.12 eV and 0.04 eV in the CdZnTe band construction, respectively. The IR transmission spectra show that when the wavenumber is larger than 1000cm^-1, the CdZnTe:In was almost opaque to the IR emission. Then its IR transmission rapidly increases to 52% when the wavenumber is decreased to 350cm^-1 and then keeps to be constant. This confirms the existence of the donor level of 0.12 eV.