Neutron detection with a silicon PIN photodiode and 6LiF converter

PIN silicon photodiodes can be used successfully for thermal neutron measurements with 6LiF converters. Tritons created in the converter are detected by the diode with high efficiency and energy resolution. An optimal separation for the triton peak from the alpha particle one is obtained with a converter about 2 μm thick. The background in these peaks due to gamma radiation or products from fast neutron reactions inside the detector is less than 1%. Experimental studies with different converter thicknesses and at different distances between the Am–Be source and the detector show good agreement with Monte Carlo simulations and with TLD measurements. The detector sensitivity is 3.2±0.5×10−3 counts in the triton peak per unit fluence of thermal neutrons.