Abstract

From electrical resistivity measurements in the range from 240 to 450 K and from optical absorption measurements the energy gap value of CuIn5Se8 has been found to be 1.13 eV. Thermally stimulated current and electrical measurements at high temperature performed in indium annealed samples show deep levels at 0.55 and 0.79 eV, respectively. These defects are expected to be associated with interstitial indium. or indium in copper site because of the In-rich condition.