Time Dependent Aspects of the Response of Some Avalanche Photodiodes to FastNeutron Irradiation

摘要

Using the fast neutron flux available from the beam collector on the RALspallation neutron source (ISI) we have irradiated the two types of avalanche photodiodes (APD) (Hamamatus S5345 (high capacitance) and the EG&G C30626E) up to a maximum fluence of 2 X 10(exp 13) neutrons per sq.cm. We report the recovery behavior of the device dark currents and noise charcteristics following exposure to the neutron flux. Using the parameters derived from these observations we model the evolution of the dark current and noise through likely CMS activity schedules.