Generation-recombination centers in p-type Hg1−xCdxTe

Abstract

Hg_1−xCd_xTe photodiodes have long been thought to be limited by recombination‐generation centers. The minority carrier lifetime τ_e in many samples of p‐type Hg_1−xCd_xTe has been explained assuming a midgap Shockley–Read center. This modeling is not unique and does not fully characterize the center. This letter reports deep level transient spectroscopy (DLTS) data on a series of x = 0.2–0.4 p‐type Hg_1−xCd_xTe samples. The DLTS data confirms the Shockley–Read model in that there is a commonly observed recombination center just below midgap. Another center near 3/4 E_g is also observed. Both of these centers can be important in controlling lifetime and detector performance.