Operating characteristics of high power, pulsed LSA oscillator diodes

Peak power of 300 watts and more at 8 GHz has been generated for 100-200 nanosecond pulses in a series of experimental LSA diodes. These devices were made of bulk, n-type Gallium Arsenide, doped to 3-5 × 10¹⁴/cm³. The GaAs samples, mounted in 1N23 crystal cartridges, are 400-800 microns thick between planar contact electrodes and have rectangular solid geometry. The variations of device performance with bias and microwave cavity adjustments, as well as with doping density and sample geometry are presented, including 10% mechanical tuning and operation over a wide range of bias from twice to eight times Gunn domain mode threshold bias.