To investigate the possibility that deep levels are associated with dislocations in narrow band gap HgCdTe, deep level transient spectroscopy has been used to studyn+hyphen;pdiodes fabricated onphyphen;type bulk Hg0.78Cd0.22Te samples with either a lsquo;lsquo;normalrsquo;rsquo; dislocation density of about 105cmminus;2or a high dislocation density of about 106cmminus;2. These samples which are gold doped with a hole concentration of 1.2times;1015cmminus;3, have a band gap of about 0.12 eV at 77 K. In samples with a lsquo;lsquo;normalrsquo;rsquo; dislocation density, a deep level of about 80 meV above the valence band was found. However, a midgap level of about 60 meV above the valence band with larger peak amplitude and broader line shapes was found in the sample with a high dislocation density.
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