Optimized spectral collection efficiency obtained in diamond-based ultraviolet detectors using a three-electrode structure

A diamond detector structure for uniform and efficient collection of photogenerated carriers in the ultraviolet spectral range is presented. The device operating principle is based on the contemporary collection of both photogenerated carriers in the bulk, and photoelectrons emitted from the diamond surface. A three-electrode device structure is used, having dual side contacts on the diamond surfaces, and a separated third electrode in the vacuum. A large improvement of the detector responsivity, as well as a compensation of the efficiency losses usually occurring for highly absorbed radiation is achieved, while keeping comparable wavelength selectivity.