Low-Cost, Low-Dose Flat Panel X-ray Detectors with a Novel Semiconductor

Project Summary Abstract After decades of advances in medical imagingx ray based imaging modalities are still the backbone of modern day general and targeted diagnostic imagingWith the advent of flat panel detector technologyflat panel x ray imagersFPXIsare now widely used in digital X ray imagingspecifically for digital radiographyfluoroscopydigital tomosynthesisimage guided radiation therapyand cone bean computed tomographyCommercial FPXIs are based on scintillators and rely on indirect conversion of x rays to photons and then to electronic signals or are based on amorphous Se semiconductor films that directly convert absorbed x rays to electronic signalThe indirect FPXIs have high detective quantum efficiencyDQEover the energy range of interestup tokVpand are used in most of the FP imaging applicationsHoweverdue to the isotropic propagation of light in the scintillatorsthese systems lack the necessary spatial resolution that is needed for other imaging applicationsOn the other handa Se based panels have excellent spatial resolution and DQEbut only up tokVpdue to low absorptivity of a Se at higher energiesThusthe use of direct conversion FPXIs is currently limited only to soft tissue applicationsIn this programwe will be developing direct conversion FPXIs with a novel photo detecting polycrystalline semiconductor demonstrating high attenuation coefficient and excellent charge transport propertiesThis semiconductor is deposited by a low temperature and low cost processThe first phase of this program will focus on the optimization of the semiconductor sensor layer structurepolycrystalline film deposition parameters and device performanceBy the end of this program we expect to have a fully functional prototype of the low dose low cost direct FPXIsuitable for transitioning to pre clinical testing NarrativeIn the proposed programwe will develop high efficiencyhigh sensitivitylow cost rugged direct flat panel X ray imagers that demonstrate homogeneous response with high spatial resolution over large areasThese nextgeneration semiconductor based flat panels are expected to increase image resolution and significantly reduce the dose requirements in imaging modalities such as digital radiographyfluoroscopytomosynthesisimageguided radiation therapyand cone bean computed tomographyThey will also open the road to high resolution low cost full body x ray imaging