Fabrication of CVD diamond photoconductive detectors

We present an investigation on the fabrication of synthetic diamond based p hoton detectors. These devices are made by depositing small gap interdigita ted contacts on polycrystalline diamond films grown by Microwave Plasma Enh anced Chemical Vapour Deposition. Gold interdigitated contacts were deposit ed on the typically rough surface of these films by using both wet etching and unconventional lift-off lithographic precesses. These detectors were te sted through X-ray irradiation in order to compare their potentialities in obtaining higher performance diamond photoconductive detectors. A better re solution was observed in samples obtained through the lift-off process. In particular for these samples the gap between electrodes could be kept very small and of the order of the grain size, giving higher response due the lo wer contribution of grain boundary effects.