Conceptual development and characterization of a diamond-based ultraviolet detector

A metal–semiconductor–metal (MSM) structure ultraviolet (UV) photodetector has been designed and fabricated on chemical vapor deposition grown diamond and its performance has been characterized. A concept was envisioned of creating a new process by which 1 μm small gap spacing was achieved. This kind of detector can be operated at a lower bias voltage with a higher photoresponsivity in the UV range. The success of this device depended on the bilayer metal electrodes, good Ohmic contact, image reversal technique, direct writing process, and sacrificial layer technology. Current–voltage and capacitance–voltage characteristics, photoresponsivity, and quantum efficiency of planar MSM structures with Au/Ti–diamond contacts are presented.