The high energy resolution of Pt/Si alpha particle detector with Al2O3 passivation layer. (December 2022)

• Record Type: Journal Article
• Authors: Wang, Bolong; Jia, Rui; Tao, Ke; Luo, Wei; Wang, Longjie; Zhang, Danni; Chen, Jiawang; Lin, ChengJian; Yang, Yun; Li, Xing; Ouyang, Xiaoping
• Is Part Of: Materials science in semiconductor processing. Volume 152(2023)
• Publication Date: 2022-12
• Subjects: Schottky type detectors -- Surface passivation -- Interface states -- A-spectrometry -- Current-voltage measurements; Semiconductors -- Periodicals; Integrated circuits -- Materials -- Periodicals; Semiconducteurs -- Périodiques; Circuits intégrés -- Matériaux -- Périodiques; Electronic journals; 621.38152
• DOI: 10.1016/j.mssp.2022.107054
• Languages: English
• ISSNs: 1369-8001

Abstract

Abstract: Schottky type detectors (STDs) are normally used to detect high-energy particles due to their excellent properties, such as simple fabrication technique, linearity, and fast-rising time. Conventional STDs cannot obtain high energy resolution due to the large leakage current working at the reverse bias condition, which is ascribed to the high interface states between metal and substrate. In this study, a thin layer of Al2 O3 (<6 nm) is innovatively inserted between metal Pt and silicon substrate to fabricate the Al2 O3 passivated Schottky type detectors. In comparison to Pt/Si, it was found that the interface states of Pt/Al2 O3 /Si could be remarkably suppressed from 10 14 eV −1 cm −2 to 10 12 eV −1 cm −2 . Thus, the lower leakage current of 5 nA was obtained with the reverse bias of 100 V, as compared to the 70 nA without the Al2 O3 passivation layer, which greatly reduced the detection noise. The α particles of 239 Pu, 241 Am, and 244 Cm are successfully detected with an energy resolution of 0.56% due to the suppression of interface states.