Gamma-ray irradiation-induced oxidation and disproportionation at the amorphous SiO/Si interfaces

• Published in: Journal of materials chemistry. C, Materials for optical and electronic devices Vol. 8; no. 47; pp. 1765 - 1773
• Main Authors: Meng, Dechao, Lan, Mu, Yang, Zeng-hui, Hu, Shouliang, Zhang, Guanghui, Liang, Chuanhui, Zhan, Haoran, Liu, Jiang, Li, Ming, Zhou, Hang, Zuo, Xu, Song, Yu, Wei, Su-Huai
• Format: Journal Article
• Published: 17.12.2020
• ISSN: 2050-7526; 2050-7534
• DOI: 10.1039/d0tc03942j

The performance of Gamma-ray irradiated silicon devices usually deteriorates due to the total ionizing dose (TID) effect. The common belief is that the TID mainly involves the change of charge states of existing point defects or defect complexes and their subsequent evolution, especially at the widely used amorphous SiO 2 (a-SiO 2 )/Si interface, but the TID is not expected to induce new structural defects and change the interface structures. We show in this paper that, contrary to the common belief, gamma-ray irradiation can lead to remarkable structural changes characterized by oxidation and disproportionation of the a-SiO 2 /Si interface. We present both experimental evidence and theoretical verification of the structural changes. The effective modulation of interfacial structures further suggests the "defective" gamma-ray to be a "constructive" defect engineering method by post-synthesis tuning of the physical performance. Distinct interfacial structure changes, including oxidation and disproportionation, have been found to be the main response to the Mrad dose gamma ray irradiation for SiO 2 /Si films.