Electron Velocity-Field Characteristics of GaxIn1-xSb Measured by a Microwave Heating Technique

The electron velocity-field (v–E) characteristics of GaxIn1-xSb in the composition range 0.4≤x≤0.9 are measured by a microwave heating technique at 35 GHz at room temperature, to study the transferred electron effect at high frequency. New microwave cavity perturbation tequnique is developed to measure a small signal conductance against the absorbed power in order to obtain the v–E curve. The results indicate that all samples except one of x=0.4, show negative differential mobility characteristics above the threshold field. The threshold field increases from 430 V/cm to 1200 V/cm and the negative mobility decreases with increasing x. For x=0.4, an impact ionization prevents from mesuring a negative differential conductivity. These results suggest that a useful Ga composition range of x for transferred electron devices is between 0.55 and 0.82, and that the response time of hot electrons is not much different from that in GaAs.