EXPERIMENTAL AND RESEARCH WORK IN NEUTRON DOSIMETRY: PHASE I. Final Summary Report, July 1, 1960 to February 28, 1961

Research was concerned with the development of a dosimeter system which will ultimately provide a capability for measuring fast-neutron dosage in terms of biological damage to personnel exposed to nuclear radiation under tactical conditions. Four areas investigated were material supplier, minority-carrier life-time in the material before processing, modifications of the processing technique to retard degradation of lifetime in processing the device, and the width of the base region of the detector. The results of experiments on devices made from highresistivity silicon, low-oxygen-content silicon, and with a deep p- p/sup +/ junction showed that none of these innovations resulted ln a significantly improved devlce. An anneallng resulted in a significantly improved device. An annealing treatment of selected detectors exposed to a fast- neutron dose of 1178 tissue rads resulted in the recovery of greater than 90% of the preirradiation characteristics. The refative scatter in the lifetimes of the 15 detectors studied in this experiment decreased appreciably after annealing above 250 deg C. Brief consideration was given to package requirements imposed by the electronic, radiological, environmental and physical properties of the detector. (auth)