SEMICONDUCTOR DETECTOR

A HAND HELD, ELECTRONIC, INTEGRATING DOSIMETER PRODUCING A REAL TIME DISPLAY, AND USING A SOLID STATE DETECTOR, IS TO BE DEVELOPED FOR THE IMMEDIATE PURPOSE OF MEASURING ABSORBED DOSE DUE TO THE VARIETY OF DIRECTLY IONIZING RADIATIONS ENCOUNTERED IN HIGH ALTITUDE AND SPACE FLIGHTS. THE CHOSEN APPROACH IS TO USE A COMPOUND SEMICONDUCTOR DETECTOR, SUCH AS CADMIUM TELLURIDE, AS A SPECTROMETER, AND TO INTEGRATETHE CHARGE PRODUCED BY THE DETECTOR AS THE INDICATOR OF THE ENERGY ABSORBED. COMPOUND SEMICONDUCTOR DETECTORS ARE SMALL IN SIZE AND LOW IN POWER CONSUMPTION; THEY ALSO OFFER SPECTROSCOPIC PERFORMANCE WITH LOW NOISE AND ACCEPTABLE RESOLUTION WHEN OPERATED AT AMBIENT TEMPERATURE. PHASE I WILL BE CONCERNED PRIMARILY WITH THE DETERMINATION OF THE FEASIBILITY OF THE PROPOSED DETECTION METHOD. IT WILL INCLUDE A SEARCH OF THE LITERATURE FOR APPLICATIONS OF COMPOUND SEMICONDUCTORSTO DOSIMETRY; CHOICE OF A CANDIDATE DETECTOR; DESIGN, FABRICATION, AND INTEGRATION OF A TEST SYSTEM FOR THE DETECTOR; ACQUISITION OF DATA FOR THE EVAULATION OF THE DETECTOR AS A DOSIMETER FOR MULTIPLE IONIZING RADIATION TYPES; EVALUATION OF THE TEST DATA FOR REQUIRED IMPROVEMENTS; AND PRELIMINARY DESIGN OF THE PROTOTYPE DOSIMETER TO BE CONSTRUCTED IN PHASE II.