Ultraviolet Sensors Using Highly-Oriented Diamond Films

Ultraviolet sensors were fabricated using undoped, highly oriented diamond (HOD) films. The sensors have a pair of interdigited electrodes of Pt or Al with the gap length of 5, 10 and, 15 microns on the HOD surfaces. Both stationary and temporal responses to irradiations of ultraviolet (UV) lights from a deuterium lamp and an ArF excimer laser (193 nm) were measured. It was found that the sensors possessed "solar-blind" property. Namely, the output signal due to a dye laser irradiation (313 nm) was only 1 % of that of the ArF laser irradiation. It was also found that the output signal due to the ArF laser irradiation well followed the incident laser pulse shape within a few nano-seconds. It was thus demonstrated that UV sensors made of HOD films can be practically used as solar-blind, robust UV laser power monitors.