Anisotropy of Critical Field in Low-Temperature Electrical Breakdown in Uncompensatedn-Type Germanium

Abstract

Distinct crystal anisotropy of the critical field in low-temperature electrical breakdown is observed on uncompensated $n$-type germanium having the donor concentration of the order of ${10}^{16}$ ${\mathrm{cm}}^{-3\mathrm{}}$. Quantitative agreement is obtained between the theory and the experiments under the assumptions that (1) intervalley scattering of electrons is negligible, (2) collision times in acoustic phonon and in neutral impurity scatterings are isotropic, and (3) conduction electrons lose their kinetic energies mainly through the neutral donor ionization process.