Fabrication of high-speed GaAs photoconductive pulse generators and sampling gates by ion implantation

An ion-implantation technique used to create high-speed photoconductive devices in semi-insulating gallium arsenide (GaAs) is described. The effects of electrical contacts, GaAs substrate material, and various implant parameters on device performance are presented. The best measured performance characteristics of sampled (correlation) waveforms are: full-width-at-half-maximum of 4.5 ps, rise time (10 to 90% of full amplitude) of 3.2 ps, and signal-to-noise ratio of approximately 50 dB (integration time is 10 ms).<
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