Electrical Properties of Cadmium Selenide Single Crystals –Effect of Heat-Treatment in Selenium Vapor–

The Hall effect and the effect of heat-treatment in selenium vapor were investigated for n-type conductive cadmium selenide single crystals. The temperature dependence of Hall coefficient showed the crystal to be nearly degenerate. The crystal had the electron concentration of 3.6×1017 cm-3 with the effective mobility of 580 cm2/V. sec. at room temperature. Heat-treatment in selenium vapor produced a rectifying layer on the crystal surface. Rectifying characteristics, barrier admittance, photoelectric effects and pulsed field effect were measured on the treated surfaces. These measurements showed that a p-type layer was formed on the n-type crystal and that the mobility of holes in the layer is about 50 cm2/V. sec. The band gap of the crystal was estimated to be 1.83 eV.