Temperature Dependence of Mobility of Warm Carriers in Germanium and Silicon

Abstract

Quadratic deviation of mobility μ due to higher electric fields (E) (μ=μ₀(1−βE²)) in germanium and silicon has been measured in the temperature range between 150°K and room temperature by a microwave (9.6 kMc) absorption method. To heat the carriers, 0.5 μ sec. and 1.0 μ sec. pulse electric fields were applied and the induced mobility change was determined from the microwave absorption.
The measured values of “warm electron coefficient” β is compared with the theories of Stratton and Adawi. It is found that the experimental results for n-type germanium agree with the theory and that no difference between high and low resistivity n-type germanium exists.
The large discrepancy between the experimental and the theoretical values in the case of p-type germanium and silicon is considered to be due to the effect of the light holes.