Influence of the operating temperature on the design and utilization of 94-GHz pulsed silicon IMPATT diodes

The RF and thermal behavior of 94-GHz P/sup +/PNN/sup +/ double drift flat doping profile silicon impact ionization avalanche transit time (IMPATT) diodes for high-power pulsed operation is investigated by means of time domain electrical oscillator models. It is demonstrated that these diodes have a limited optimum temperature range of operation, associated to specific matching and bias conditions, to achieve a stable and high power operation. This restriction necessitates a thermal control when the oscillator must operate over a wide ambient temperature range. Highly doped, short active zone length diodes appear to have the best potential for high power performance.