Amorphous Silicon Sensor Arrays for Radiation Imaging

Large two-dimensional a-Si:H imaging arrays have applications in imaging of X-ray, gamma-ray and charged particle fluxes. Radiation imaging using a-Si:H p i n sensors together with a phosphor to transform the radiation into visible light is described, and some examples of images are shown. These arrays are very efficient in imaging large area diffuse sources, and the a-Si:H sensors have little radiation damage. The main limitation to the sensitivity of the array is the leakage current of the sensors, which is a source of noise and limits the integration time of the arrays. The contributions to the leakage current from bulk thermal generation and contact injection are discussed