Shallow-donor ionization energies in the II-VI compounds

Abstract

Hall data on ZnSe, CdS, CdSe, and CdTe have been analyzed to determine the shallow-donor ionization energies ${E}_{d}$ and the total donor and acceptor impurity concentrations ${N}_{d}$ and ${N}_{a}$, respectively. Lowering of the ${E}_{d}$ values owing to impurity concentration effects are noted even in the purest samples. When the data are analyzed using linear plots of ${E}_{d}$ vs ${({N}_{{d}^{+}})}^{\frac{1}{3}}$, the resulting values of the ionization energy for infinite dilution are in good agreement with optical data and with the hydrogenic model.