Defect related absorption in p-type Hg1−xCdxTe Alloys

Abstract

Infrared absorption in undoped p‐type Hg1−xCdxTe and Cd1−xMnxTe alloys is measured in the temperature range of 77 to 300 K. Defect related absorption is observed in both, Hg1−xCdxTe (x > 0.3) and Cd0.9Mn0.1Te alloys at low temperature. Annealing and Sb doping are used to identify the absorption mechanism. The defect related absorption is attributed to the transition from the valence band to an acceptor level. A quantum defect model is used to fit the absorption spectra and to obtain the ionization energy of the defect. The level between 15 meV and 0.4 Eg is observed in undoped p‐type Hg1−xCdxTe alloys.