Perforated Semiconductor Neutron Detector Modules for Detection of Spontaneous Fission Neutrons

Compact neutron detectors are being designed and tested for use as low-power real-time personnel dosimeters and for remote neutron sensing. The neutron detectors are pin diodes that are mass produced from high-purity Si wafers. Each detector has thousands of circular perforations etched vertically into the device. The perforations are backfilled with ⁶LiF to make the pin diodes sensitive to thermal neutrons. The prototype devices delivered over 3.8% thermal neutron detection efficiency while operating on only 15 volts. The highest efficiency devices thus far have delivered over 12% thermal neutron detection efficiency. Devices moderated with high density polyethylene (HDPE) can be used for fast neutron detection. Compact packages with or without remote readout electronics are under construction and characterization.