Characterization of ion damage on p-type cadmium telluride surfaces

The effects of low-energy Ar ions (0–800 eV), from an ion beam and in an rf sputtering unit on the surface of single-crystal p-type CdTe have been investigated as a function of the ion energy using measurements of current versus voltage, spectral response, and capacitance versus voltage for indium junctions on CdTe. A threshold for the effects has been identified at an accelerating voltage of slightly less than 100 V for a fluence of 5×10−3C cm−2. Bombardment by Ar ions at voltages larger than this results in formation of an n-type surface layer on the p-type CdTe crystals.