In order to test the suggestion that deep levels were associated with dislocations in narrow band-gap materials, deep-level transient spectroscopy was used to study n+-p diodes which had been fabricated on p-type bulk Hg0.78Cd0.22Te samples that had a dislocation density of 105 (normal) or 106/cm2 (high). It was found that those samples which were Au-doped, with a hole concentration of 1.2 x 1015/cm3, had a band gap of about 0.12eV at 77K. In samples with a normal dislocation density, a deep level was found at about 0.08eV above the valence band. A mid-gap level at about 0.06eV above the valence band (with larger peak amplitude and broader line-shape) was found in samples with a high dislocation density.

M.C.Chen, R.A.Schiebel: Journal of Applied Physics, 1992, 71[10], 5269-71