Abstract: A method for detecting single photons of high energy radiation using a detector comprising an array of pixels, each pixel including a charge receptive substrate. The method includes the operations of capturing high energy photons with the pixel array, collecting the charges generated in each pixel by the charge receptive substrate of that pixel, reading out the collected charges and analyzing the read out charges. In addition, a system for detecting single photons of high energy radiation is described. The system includes a pixel array in which each pixel includes a polycrystalline photoconductive film deposited on a charge receptive substrate. The system further includes low noise electronics for reading out the charges generated by high energy photons when the latter interact with the film. Additionally, the system includes a data processor in communication with the low noise electronics.

Abstract: An imaging composition for radiation detection systems which includes an admixture of at least one non-heat treated, non-ground particulate semiconductor with a polymeric binder. The non-heat treated, non-ground particulate semiconductor is selected from mercuric iodide, lead iodide, bismuth iodide, thallium bromide and cadmium-zinc-telluride (CZT), and at least 90% of the semiconductor particulates have a grain size of less than 100 microns in their largest dimension. A radiation detector plate (10) for an imaging system includes a substrate (12) which serves as an electrode, at least one imaging composition layer (16) applied onto the substrate (12), and a second electrode (18) which is in electrical connection with the imaging composition (16) and connected (20, 22) to a high voltage bias.

Abstract: A radiation detection and imaging system, which includes at least one radiation detecting and imaging element comprising a planar substrate, a surface of which has been seeded with mercuric iodide grains having a diameter in the range of about 0.01-1.0 micron, before being subjected to a step of deposition thereon of a layer of polycrystalline mercuric iodide having a thickness of up to about 3000 microns. A process for preparing an element such as the one described. A planar substrate, wherein a surface thereof has been seeded with mercuric iodide grains having a diameter in the range of about 0.01-1.0 micron. A physical vapor deposition method for preparing a radiation detecting and imaging element comprising a planar substrate by deposition of a film of mercuric iodide having a maximum thickness of about 3000 microns on a surface on the substrate.

Abstract: A photolithographic process forms patterns on HgI2 surfaces and defines metal sublimation masks and electrodes to substantially improve device performance by increasing the realizable design space. Techniques for smoothing HgI2 surfaces and for producing trenches in HgI2 are provided. A sublimation process is described which produces etched-trench devices with enhanced electron-transport-only behavior.

Abstract: An element adapted for at least one use selected from high energy radiation detection, imaging and barrier use, which includes a planar substrate on a surface of which there is a layer polycrystalline mercuric iodide, which has been deposited from the vapor phase, having a thickness within the range of from more than 0.5 mm and up to about 10 mm. A process for preparing an element having such thicknesses. A planar substrate, having deposited on a surface thereof, a layer of mercuric iodide in at least two discrete adjacent sub-layers having a total thickness within the range of from greater than 0.5 mm to about 10 mm. A system adapted for at least one purpose selected from radiation detection, radiation imaging and high energy absorption, which includes an element having thicknesses as described above.

Abstract: A continuous multi-layer construction for detecting radiation including a polymer layer, a conducting electrode layer affixed to the polymer layer and a particle-in-binder composite layer affixed to the conducting electrode layer, where the composite layer absorbs photons. A process for fabricating continuous multi-layer constructions for detection of radiation including the following steps: depositing a conducting electrode layer onto a polymer film, applying at least one coating layer of a particle-in-binder composite onto the conducting electrode layer, and drying the at least one coating layer of the particle-in-binder composite.

Abstract: A method for detecting single photons of high energy radiation using a detector comprising an array of pixels, each pixel including a charge receptive substrate. The method includes the operations of capturing high energy photons with the pixel array, collecting the charges generated in each pixel by the charge receptive substrate of that pixel, reading out the collected charges and analyzing the read out charges. In addition, a system for detecting single photons of high energy radiation is described. The system includes a pixel array in which each pixel includes a polycrystalline photoconductive film deposited on a charge receptive substrate. The system further includes low noise electronics for reading out the charges generated by high energy photons when the latter interact with the film. Additionally, the system includes a data processor in communication with the low noise electronics.

Abstract: A method for reducing the leakage current in CZT crystals, particularly Cd.sub.1-x Zn.sub.x Te crystals (where x is greater than equal to zero and less than or equal to 0.5), and preferably Cd.sub.0.9 Zn.sub.0.1 Te crystals, thereby enhancing the ability of these crystal to spectrally resolve radiological emissions from a wide variety of radionuclides. Two processes are disclosed. The first method provides for depositing, via reactive sputtering, a silicon nitride hard-coat overlayer which provides significant reduction in surface leakage currents. The second method enhances the passivation by oxidizing the CZT surface with an oxygen plasma prior to silicon nitride deposition without breaking the vacuum state.