A novel detection scheme for large area imaging of low energy X-rays using amorphous silicon technology

We report a novel low voltage direct detection scheme for low energy X-rays using hydrogenated amorphous silicon (a-Si:H) thin film heavy metal, e.g. molybdenum (Mo), Schottky diodes. Preliminary characterization, for a broad range of bias conditions and detector geometries, illustrates the design trade-offs needed to optimize performance with respect to stability, charge leakage, noise, X-ray sensitivity, and spatial resolution. For a 200 μm square detector, the measured number of electrons, for a 500 ms X-ray exposure, ranged from 10⁷ to 10⁸ in the 20 to 100 keV energy range. separation and collection