PURPOSE: The feasibility of a practical solid-state technology for low photon flux imaging applications was investigated. The technology is based on an amorphous selenium photoreceptor with a voltage-controlled avalanche multiplication gain. If this photoreceptor can provide sufficient internal gain, it will be useful for an extensive range of diagnostic imaging systems. METHODS: The avalanche photoreceptor under investigation is referred to as HARP-DRL. This is a novel concept in which a high-gain avalanche rushing photoconductor (HARP) is integrated with a distributed resistance layer (DRL) and sandwiched between two electrodes. The avalanche gain and leakage current characteristics of this photoreceptor were measured. RESULTS: HARP-DRL has been found to sustain very high electric field strengths without electrical breakdown. It has shown avalanche multiplication gains as high as 10(4) and a very low leakage current (< or = 20 pA/mm2). CONCLUSIONS: This is the first experimental demonstration of a solid-state amorphous photoreceptor which provides sufficient internal avalanche gain for photon counting and photon starved imaging applications.
PURPOSE: The feasibility of a practical solid-state technology for low photon flux imaging applications was investigated. The technology is based on an amorphous selenium photoreceptor with a voltage-controlled avalanche multiplication gain. If this photoreceptor can provide sufficient internal gain, it will be useful for an extensive range of diagnostic imaging systems. METHODS: The avalanche photoreceptor under investigation is referred to as HARP-DRL. This is a novel concept in which a high-gain avalanche rushing photoconductor (HARP) is integrated with a distributed resistance layer (DRL) and sandwiched between two electrodes. The avalanche gain and leakage current characteristics of this photoreceptor were measured. RESULTS: HARP-DRL has been found to sustain very high electric field strengths without electrical breakdown. It has shown avalanche multiplication gains as high as 10(4) and a very low leakage current (< or = 20 pA/mm2). CONCLUSIONS: This is the first experimental demonstration of a solid-state amorphous photoreceptor which provides sufficient internal avalanche gain for photon counting and photon starved imaging applications.
Authors: Wei Zhao; Dan Li; Alla Reznik; B J M Lui; D C Hunt; J A Rowlands; Yuji Ohkawa; Kenkichi Tanioka Journal: Med Phys Date: 2005-09 Impact factor: 4.071
Authors: Safa Kasap; Joel B Frey; George Belev; Olivier Tousignant; Habib Mani; Jonathan Greenspan; Luc Laperriere; Oleksandr Bubon; Alla Reznik; Giovanni DeCrescenzo; Karim S Karim; John A Rowlands Journal: Sensors (Basel) Date: 2011-05-09 Impact factor: 3.576