Characterization of polycrystalline diamond films grown by Microwave Plasma Enhanced Chemical Vapor Deposition (MWPECVD) for UV radiation detection

Photodetectors based on polycrystalline diamond (PCD) films are of great interest to many researches for the attractive electronic, mechanical, optical and thermal properties. PCD films are grown using the Microwave Plasma Enhanced Chemical Vapor Deposition (MWPECVD) method. First, we characterized films by means of structural and morphological analysis (Raman spectroscopy and scanning electron microscopy), then we evaporated a pattern of coplanar interdigitated Cr/Au contacts with an inter-electrode spacing of 100 um in order to perform the electrical characterization.We carried out measurements of dark current and impedance spectroscopy to investigate the film properties and conduction mechanisms of films and the effects of post-growth treatments. Finally we developed a charge sensing pre-amplifier to read-out the signal produced by UV photons in the detector.