Evaluation parameters rate of change of the microwave bipolar transistor operated in the high mode

Calculated rate of change of topological parameters (width and doping level of the base as well as the coefficient of heterogeneity) bipolar p-n-p-transistor, designed for operation at temperatures T = [500-700] K. The estimation of the degradation rate of operating parameters of the device. It is shown, that stable enough high-level transistor must have at least base doping k = 8,62*10 -5 eV/K at a sufficient depth of its occurrence.