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arXiv · 1505.01827

Crystal growth and detector performance of large size high-purity Ge crystals

Guojian Wang·Mark Amman·Hao Mei·Dongming Mei·Klaus Irmscher·Yutong Guan·Gang Yang
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Abstract

High-purity germanium crystals approximately 12 cm in diameter were grown in a hydrogen atmosphere using the Czochralski method. The dislocation density of the crystals was determined to be in the range of 2000 - 4200 cm-2, which meets a requirement for use as a radiation detector. The axial and radial distributions of impurities in the crystals were measured and are discussed. A planar detector was also fabricated from one of the crystals and then evaluated for electrical and spectral performance. Measurements of gamma-ray spectra from Cs-137 and Am-241 sources demonstrate that the detector has excellent energy resolution.

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Guojian Wang, Mark Amman, Hao Mei, Dongming Mei, Klaus Irmscher, Yutong Guan, Gang Yang. 2015-05-07. Crystal growth and detector performance of large size high-purity Ge crystals. https://arxiv.org/abs/1505.01827

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