Pulsed and CW Double-Drift Silicon IMPATTs

The properties of double-drift Si IMPATTs designed for both pulsed and CW operation at frequencies between 8 and 18 GHz are discussed. Peak pulse powers greater than 18 watts at 10 GHz and 13.5 watts at 16.5 GHz were obtained for 800 nsec pulses at a 25% duty cycle with the junction temperature rise limited to 200/spl deg/C. For a similar temperature rise a CW power of 3.4 watts at 11.5 GHz was achieved. Conversion efficiencies were between 10.5 and 13.7%.