Search results for "Cadmium alloys"
showing 3 items of 3 documents
High-energy X-ray diffraction and topography investigation of CdZnTe
2005
High-energy transmission x-ray diffraction techniques have been applied to investigate the crystal quality of CdZnTe (CZT). CdZnTe has shown excellent performance in hard x-ray and gamma detection; unfortunately, bulk nonuniformities still limit spectroscopic properties of CZT detectors. Collimated high-energy x-rays, produced by a superconducting wiggler at the National Synchrotron Light Source’s X17B1 beamline, allow for a nondestructive characterization of thick CZT samples (2–3 mm). In order to have complete information about the defect distribution and strains in the crystals, two series of experiments have been performed. First, a monochromatic 67 keV x-ray beam with the size of 300×3…
Spectroscopic response and charge transport properties of CdZnTe detectors grown by the vertical Bridgman technique
2015
In this work, we present the results of spectroscopic investigations on CdZnTe (CZT) detectors grown by the boron oxide encapsulated vertical Bridgman technique (1MEM-CNR, Parma, Italy). The detectors, with different thicknesses (1 and 2.5 mm), are characterized by the same electrode layout (gold electroless contacts): the anode is a central electrode (2 x 2 mm(2)) surrounded by a guard-ring electrode, while the cathode is a planar electrode covering the detector surface (4.1 x 4.1 mm(2)). The results of electrical investigations point out the low leakage currents of these detectors even at high bias voltages: 38 nA/cm(2) (T = 25 degrees C) at 10000 V/cm. The time stability and the spectros…
Material quality characterization of CdZnTe substrates for HgCdTe epitaxy
2006
Cd1−xZnxTe (CZT) substrates were studied to investigate their bulk and surface properties. Imperfections in CZT substrates affect the quality of Hg1−xCdxTe (MCT) epilayers deposited on them and play a role in limiting the performance of infrared (IR) focal plane arrays. CZT wafers were studied to investigate their bulk and surface properties. Transmission and surface x-ray diffraction techniques, utilizing both a conventional closed-tube x-ray source as well as a synchrotron radiation source, and IR transmission micro-spectroscopy, were used for bulk and surface investigation. Synchrotron radiation offers the capability to combine good spatial resolution and shorter exposure times than conv…