Picosecond response of carbon doped InGaP photoconductive gate

To minimize the effect of the dark current of a photoconductive gate, adopting the wide bandgap material is a simple solution. Highly resistive carbon doped InGaP can be an alternative material to the conventional low temperature MBE grown GaAs. But its photoresponse has not been evaluated. The temporal response of the photoconductive gate, which was formed on the MOCVD grown carbon doped InGaP, was measured. The measured response was compared with that on the LT-GaAs. The lifetime of the carrier was estimated to be about several tens of picoseconds. Therefore, this material has a possibility to suit for the high-speed photoconductive sampling application.