Development of Neutron Transmutation Doped Germanium (NTD-Ge) for Cryogenic Applications
Abstract
This paper presents the systematic fabrication and characterization of cryogenic thermometers based on neutron transmutation-doped germanium (NTD-Ge). High-purity (10N) germanium samples were irradiated by thermal neutrons with different fluences at the China Advanced Research Reactor (CARR). After irradiation and a six-month cooling-down period, positron annihilation lifetime spectroscopy and temperature-dependent Hall effect measurements were performed to characterize irradiation-induced defects and carrier concentrations in the NTD-Ge samples. Utilizing standard semiconductor fabrication techniques, point electrodes were deposited onto the processed samples to fabricate functional NTD-Ge cryogenic thermometers. The low-temperature resistance performance of the devices was characterized down to 20 mK on a millikelvin range cryogenic test platform. The measured temperature dependence of resistance follows Mott's law, showing excellent agreement across the full measured range. The extracted T0 is consistent with expectations. These results collectively verified both the applicability of the thermometers in cryogenic system and the reliability of the fabrication procedure.
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BibTeX
@misc{zhao2026development,
title = {{Development of Neutron Transmutation Doped Germanium (NTD-Ge) for Cryogenic Applications}},
author = {Kangkang Zhao and Mingxuan Xue and Haiping Peng and Deyong Duan and Yunlong Zhang and Yi Li and Junfeng Yang and Xintan Deng and Hongjun Zhang and Huaichang Ran and Sicheng Wen and Xiaolian Wang and Zizong Xu},
howpublished = {arXiv},
year = {2026},
month = sep,
doi = {10.48550/arxiv.2608.21392},
eprint = {2608.21392},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2608.21392},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Development of Neutron Transmutation Doped Germanium (NTD-Ge) for Cryogenic Applications
AU - Kangkang Zhao
AU - Mingxuan Xue
AU - Haiping Peng
AU - Deyong Duan
AU - Yunlong Zhang
AU - Yi Li
AU - Junfeng Yang
AU - Xintan Deng
AU - Hongjun Zhang
AU - Huaichang Ran
AU - Sicheng Wen
AU - Xiaolian Wang
AU - Zizong Xu
PY - 2026
DA - 2026/09/30
PB - arXiv
DO - 10.48550/arxiv.2608.21392
UR - https://arxiv.org/abs/2608.21392
AB - This paper presents the systematic fabrication and characterization of cryogenic thermometers based on neutron transmutation-doped germanium (NTD-Ge). High-purity (10N) germanium samples were irradiated by thermal neutrons with different fluences at the China Advanced Research Reactor (CARR). After irradiation and a six-month cooling-down period, positron annihilation lifetime spectroscopy and temperature-dependent Hall effect measurements were performed to characterize irradiation-induced defects and carrier concentrations in the NTD-Ge samples. Utilizing standard semiconductor fabrication techniques, point electrodes were deposited onto the processed samples to fabricate functional NTD-Ge cryogenic thermometers. The low-temperature resistance performance of the devices was characterized down to 20 mK on a millikelvin range cryogenic test platform. The measured temperature dependence of resistance follows Mott's law, showing excellent agreement across the full measured range. The extracted T0 is consistent with expectations. These results collectively verified both the applicability of the thermometers in cryogenic system and the reliability of the fabrication procedure.
ER -