Characterization of new a-Si:H Detectors fabricated from Amorphous Silicon deposited at High Rate by Helium enhanced PECVD

This paper is concerned with the characterization of new detectors fabricated from a-Si:H films deposited at high rates through the dilution of SiH4 in Helium by PECVD (Plasma Enhanced Chemical Vapor Deposition) technique. Rates up to ten times (5.5 µm/h) that of the standard technique are obtained. We have investigated the electrical characteristics depletion voltage, residual space charge density- of the helium diluted material and compared them to that of the standard material. Finally, the response of detectors, fabricated from both materials, to 5.5 MeV alpha particles are compared.