Signal Generation due to Alpha Particle in Hydrogenated Amorphous Silicon Radiation Detectors

Abstract

The hydrogenated amorphous silicon (a-Si:H) holds good promise for radiation detection from its inherent merits over crystalline counterpart. For the application to alpha spectroscopy, the induced charge collection in a-Si:H pin detector diodes was simulated based on a relevant non-uniform charge generation model. The simulation was performed for the initial energy and the range of incident alpha particles, detector thickness and the operational parameters such as the applied reverse bias voltage and shaping time. From the simulation, the toal charge collection was strongly affected by hole collection as expected. To get a reasonable signal generation, therefore, the hole collection should be seriously considered for detector operational parameters such as shaping time and reverse voltage etc. For the spectroscopy of alpha particle from common alpha sources, the amorphous silicon should have about 70 m thickness.