Diamond UV Detector with Graphite Electrodes Formed by Laser Ablation

A Diamond being a wide-bandgap radiation-hard semiconductor, is rather promising for the development of UV detectors, including the solar-blind ones. A version of an all-carbon UV detector has been implemented on a single-crystal CVD diamond wafer with the interdigital electrodes consisting of a system of shallow (near-surface) and deep graphitized grooves produced by laser ablation without any lithography. Simulation of the electric field distribution in the detector has demonstrated the advantage of using buried electrodes that provide a more uniform field distribution within the crystal. The photosensitivity spectra exhibit a sharp peak at 220 nm, with the buried electrodes providing a 75% higher response amplitude (14 A/W).