The Dependence of Cd Diffusion and Electrical Conductivity in CdS on Cd Partial Pressure and Temperature

The diffusion coefficient of Cd in undoped single crystal CdS has been measured at 850 °C as a function of Cd pressure, p Cd , by a radiotracer method. The electrical conductivity of similar CdS samples has also been measured as a function of p Cd in the temperature range 660 to 950 °C. It is concluded that the defects V″ Cd and Cd are responsible for Cd diffusion at 850 °C and that a satisfactory account of the results can be given in terms of Cd interstitials and vacancies plus a residual shallow foreign donor. A model for the defect structure in CdS at 850 °C is presented in terms of Cd vacancies and interstitials.