High-efficiency single-drift GaAs IMPATT diodes for 72 GHz

High-efficiency GaAs single-drift IMPATT diodes have been developed up to 72 GHz using molecular-beam epitaxy. The design of the devices is based on a lower value of the electron drift velocity at high electric fields. The diodes are bonded on diamond heat sinks. The best efficiencies are 12.5% at 63 GHz with 450 mW output power and 10% at 72 GHz with 350 mW output power.