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arXiv · 2409.18555

Defect detection and size classification in CdTe samples in 3D

M. Väänänen·M. Kalliokoski·R. Turpeinen·M. Bezak·P. Luukka·A. Karjalainen·A. Karadzhinova-Ferrer
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Abstract

Defects in semiconductor crystals can have significant detrimental effects on their performance as radiation detectors. Defects cause charge trapping and recombination, leading to lower signal amplitudes and poor energy resolution. We have designed and built a modular 3D scanner for analyzing these defects in semiconductor samples using commercial off-the-shelf components. Previous solutions offer great spatial resolution, but have limited sample holding capacity and use continuum light sources which can cause difficulty differentiating between different materials within samples. Our design also includes a modular sample holder allowing for easy changing of samples. In this paper, we showcase first results achieved with this custom built scanner as well as planned developments.

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M. Väänänen, M. Kalliokoski, R. Turpeinen, M. Bezak, P. Luukka, A. Karjalainen, A. Karadzhinova-Ferrer. 2024-09-27. Defect detection and size classification in CdTe samples in 3D. https://arxiv.org/abs/2409.18555

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