Effect of contacts on the counting characteristics of heavily doped n-type cadmium

Cadmium telluride single crystals were grown heavily doped with chloride by the THM method. The resulting crystals were n-type with free carrier concentrations of the order of 1012/cm at room temperature. Hall effect studies revealed room temperature mobilities between 30 and 350 cm2/v-sec and resistivities between 2 x 103 and 104 ohm-cm. Studies were made of the gamma and alpha counting characteristics of these crystals with metal, metal-semiconductor, and metal-insulator electrodes. It was found that the MIS and MSS structures resulted in significant improvement over the MS structures in counting, signal-to-noise and energy resolution