Doping-induced bandwidth enhancement in metal-semiconductor-metal photodetectors

A novel technique is demonstrated for enhancing metal-semiconductor-metal photodetector bandwidths without reducing responsivity. The authors have observed bandwidth increases of up to 10 GHz from control to enhanced photodetectors which corresponds to about 70% enhancement. This technique involves modifying the internal electric field structure, by introducing a buried n-type doped layer that is completely depleted, to reduce the relatively long hole transit time.>