FOR SOME TIME SILICON AVALANCHE PHOTODETECTORS HAVE BEEN RECOGNIZED AS POTENIALLY HAVING SIGNIFICANT TECHNICAL ADVANTAGES OVER EXISTING DEVICES USED FOR PARTICLE AND CVCMA-RAY DETECTION WITH SCINTILLATOR CRYSTALS.

FOR SOME TIME SILICON AVALANCHE PHOTODETECTORS HAVE BEEN RECOGNIZED AS POTENIALLY HAVING SIGNIFICANT TECHNICAL ADVANTAGES OVER EXISTING DEVICES USED FOR PARTICLE AND CVCMA-RAY DETECTION WITH SCINTILLATOR CRYSTALS. THESES ADVANTAGES - COMPACTNENN, SOLID-STATE STABILITY, ROOM TEMPERATURE OPERATION, HIGH INTERNAL GAIN AND INSENSITIVITY TO MAGNETIC FIELDS - WOULD MAKE THEM AN IDEAL CHOICE DETECTOR IN MANY HIGH ENERGY PHYSICS APPLICATIONS. SUCH SENSORS COULD REDUCE THE SIZE AND COMPLEXITY, AND ULTIMATELYTHE COST, OF MODERN DETECTOR SYSTEMS. IN ADDITION, THEY WOULD OFFER THE POSSIBILITY OF FABRICATING COMPACT, HIGH SPATIAL RESOLUTION, MULTI-ELEMENT ARRAYS. UTILIZATION OF SILICON AVALANCHE DETECTORS FOR THIS APPLICATION HAS BEEN INHIBITED IN THE PAST BY SEVERAL TECHNICAL PROBLEMS RELATED TO SMALL SIZE, LOW INTERNAL GAIN, AND VERY POOR SENSITIVITY AT THE WAVELENGHTS AT WHICH BGO AND OTHER IMPORTANT SCINTALLATORS EMIT LIGHT. HOWEVER, UNDER A RECENT PROGRAM TOEXAMINE THE FEASIABILITY OF MAKING LARGE AREA LOW NOISE AVALANCHE DIODES FOR USE WITH NAI AS GAMMA DETECTORS, THESES LIMITATIONS HAVE PARTIALLY BEEN OVERCOME. ONE-INCH DIAMETER DETECTORS WITH USEFUL INTERNAL GAIN AND GOOD SENSITIVITY TO THE SHORT WAVELENGTH LIGHT EMITTER BY NAI HAVE BEEN SUCESSFULLY FABRICATED. THAT PROGRAM DEMONSTRATED THAT LARGE AREA, BLUE SENSITIVE SIAPD DEVICES CAN BECOME A REALITY. RESEARCH IS NOW REQUIRED TO IMPROVE PERFORMANCE AND EXAMINE THE ULTIMATE CAPABILITIES OF THE DEVICE. IN ADDITION, LARGE AREA SIAPD DEVICES SHOULD ALLOW FOR EXCEPTIONAL ARRAY DETECTORS. THEREFORE, THE PROPOSED PROGRAM WILL INVESTIGATE THE FEASIABILITY OF USING THESE DEVICES IN HIGH ENERGY PHYSICS EXPERIMENTS AND EXAMINE WAYS TO IMPROVE DEVICE PERFORMANCE, SIZE AND STRUCTURE IN ORDER TO MAKE THESE DEVICES A PRACTICAL REALITY.