Low dark-current germanium-on-silicon near-infrared detectors

We demonstrate near-infrared Ge-on-Si photodiodes designed to minimize the dark current density and fabricated by chemical vapor deposition. The p-i-n detectors exhibit record low dark currents of 7 nA at 1-V reverse bias with responsivities close to the theoretical maximum. An excellent performance is ascertained,even for very low reverse voltages