Hall and Drift Mobilities; Their Ratio and Temperature Dependence in Semiconductors

It is shown that the Hall and drift mobilities in the temperature range in which scattering by ionized impurities dominates should exhibit a temperature dependence less rapid than T3/2. This conclusion is in agreement with experimental observation. Furthermore, the mobility ratio, μHμd, is not equal to 315π512 nor is it independent of temperature. Instead, μHμd only approaches 315π512 at very high temperatures and decreases monotonically to 3π8 as the temperature is lowered.