Author/Authors :
Hermon، نويسنده , , H and Schieber، نويسنده , , M and James، نويسنده , , R.B and Antolak، نويسنده , , A.J and Morse، نويسنده , , D.H and Brunett، نويسنده , , B and Hackett، نويسنده , , C and Tarver، نويسنده , , E and Komar، نويسنده , , V and Goorsky، نويسنده , , M.S and Yoon، نويسنده , , H and Kolesnikov، نويسنده , , N.N and Toney، نويسنده , , J and Schlesinger، نويسنده , , T.E، نويسنده ,
Abstract :
Vertical high-pressure Bridgman (VHPB) Cd1-xZnxTe (0.04<x<0.24) detector crystals grown in the Ukraine and Russia have been evaluated and compared to US-grown materials. Various analytical techniques were used to study the materials for trace impurities, precipitates, crystallinity, and electrical transport properties. Relatively, high concentrations of carbon and trace impurities such as Se, Nd and Si have been detected in the crystals. In most cases, the crystals showed lower resistivity than US-grown CZT. However, recent crystals grown in Russia exhibited better detector performance than those grown previously, and a good response to an 241Am radioactive source was found. Electron lifetimes below 1 μs were measured in crystals having significant numbers of micro-defects, compared to lifetimes of 5–15 μs found in spectrometer grade materials produced in the US. Furthermore, the zinc composition along the growth axis showed better homogeneity in comparison with the US material.
Keywords :
Crystal growth , elemental analysis , Transient charge technique (TC , Vertical high-pressure Bridgman (VHPB) , Cadmium zinc telluride (CZT) , Room-temperature radiation detectors , Photoluminescence (PL) , Particle-induced X-ray emission (PIXE) , X-Ray Diffraction (XRD)
