Electron Scattering by Neutralized Acceptors in Germanium. II. Zinc

Abstract

Electron scattering by neutralized zinc acceptors in germanium has been studied between 1.5 and 4.2°K through the cyclotron resonance technique under the application of uniaxial compressional stress. Without stress, it is found, the carrier lifetime in zinc-doped germanium becomes so short that the cyclotron resonance linewidth appreciably suffers from the lifetime broadening. Application of uniaxial stress, however, drastically increases the electron lifetime, and analyses of the electron resonance signals with and without stress show that zinc, the dopant itself, is responsible for such a short lifetime. The scattering relaxation time of electrons by neutral zinc impurities is thus derived only under a high stress limit applied in order to avoid mixing of the lifetime broadening. The derived value agrees in a rather surprising manner with the theoretical one based on the positron-helium atom scattering model after Kestner et al.