CdTe and CZT materials are technologies for gamma and x-ray imaging for applications in industry, homeland security,
defense, space, medical, and astrophysics. There remain challenges in uniformity over large detector areas (50~75 mm)
due to a combination of material purity, handling, growth process, grown in defects, doping/compensation, and metal
contacts/surface states. The influence of these various factors has yet to be explored at the large substrate level required
for devices with higher resolution both spatially and spectroscopically. In this study, we looked at how the crystal
growth processes affect the size and density distributions of microscopic Te inclusion defects. We were able to grow
single crystals as large as 75 mm in diameter and spatially characterize three-dimensional defects and map the
uniformity using IR microscopy. We report on the pattern of observed defects within wafers and its relation to
instabilities at the crystal growth interface.
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