Electromigration of Mobile Defects in CdTe

Electromigration of mobile charged defects in external electric field is investigated at various temperatures and biases in conductive undoped and semiinsulating In-doped CdTe, respectively. A set of electric contacts as potential probes arranged linearly along the sample was used for the detection of the drift of the local resistance modulation. The observed modulation drifting along the sample always from the positive toward negative contact after step-like bias polarity reversion points to the migration of positively charged point defects. Mobility and diffusion coefficient of mobile defects at 100degC and 600degC, respectively are determined. Electromigration of point defects is also tested by low temperature photoluminescence and a model explaining migration of charged defects is suggested.