Density functional calculations were used to study both intrinsic and extrinsic defects in AlSb. Attention was focussed on the carrier compensation and trapping properties of these defects, which were important in radiation detection applications. It was shown that the Sb antisite (SbAl) was a low-energy defect, with interesting property of light-induced metastability, similar to the As antisite in GaAs. The SbAl was effective in compensating holes induced by the residual carbon but was also a deep electron trap that reduces the carrier drifting length. The possibility was considered of using hydrogenated isovalent N impurity in AlSb and GaAs to pin the Fermi level without causing efficient carrier trapping.

Defects in AlSb - a Density Functional Study. M.H.Du: Physical Review B, 2009, 79[4], 045207