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Next-Generation Visible Light Photon Counters--Lawrence Semiconductor Research Laboratory, Inc., 2300 West Huntington Drive, Tempe, AZ  85282-3130; 602-438-2300

Dr. McDonald Robinson, Principal Investigator, mac-robinson@LSRL.com 

Dr. Lamonte Lawrence, Business Official, montelawrence@cs.com 

DOE Grant No. DE-FG03-01ER83261

Amount:  $747,545

The successful development of high quality plastic wavelength-shifting optical fibers coupled to a plastic scintillator for nuclear and high energy particle detection applications has created a need for compact, high-gain, high efficiency detectors in the visible and near-infrared.  Visible light photon counters (VLPCs), fabricated several years ago, showed significant promise but suffered from significant variations in gain.  This project will utilize epitaxial process expertise to develop a new generation of VPLCs with improved properties, including much narrower gain dispersion and lower cost.  In Phase I, eighty 5-inch wafers were produced, 10 each of 8 different combinations of donor and acceptor doping.  Low defect density and excellent uniformity were demonstrated.  In Phase II, visible light photon counters will be fabricated from the Phase I wafers and tested.  Based on the results, the design will be modified and a second round of epitaxial wafers will be grown.  Devices fabricated from the second round will be provided to end-users. 

Commercial Applications and Other Benefits as described by the awardee:  Applications for visible light photon counters in combination with plastic scintillator include electromagnetic and hadronic calorimetry, shower max detectors, preshower detectors, photon vetos, large-scale neutrino detectors, muon hodoscopes, and high resolution tracking systems.