Complementarily doped metal-semiconductor interfaces to reduce dark current in MSM photodetectors

摘要

Metal-Semiconductor-Metal ("MSM") photodetectors and methods to fabricate thereof are described. The MSM photodetector includes a thin heavily doped ("delta doped") regions deposited at an interface between metal contacts and a semiconductor layer to reduce a dark current of the MSM photodetector. Band engineering at the metal-semiconductor interfaces using complementarily delta doped semiconductor regions to fix two different interface workfunctions. Delta doping the grounded contact interface with p+ and the reverse biased interface with n+ enhances the Schottky barrier faced by both electrons and holes at the point of injection from source contact into the channel and at the point of collection from the channel into the drain contact.