Paper

Radiation damage study of Belle II silicon strip sensors with 90 MeV electron irradiation

Behera, P K, Tanaka, S, Serrano, J, Finck, C, Zeng, F, Bahinipati, S, Bozek, A, Gabrielli, A, Mondal, S, Yin, H, Shimasaki, T, Tsuboyama, T, Onuki, Y, Thalmeier, R, Kaliyar, A B, Aihara, H, Bettarini, S, Buchsteiner, F, Sato, Y, Lisovskyi, V, Belle II SVD Collaboration, Corona, L, ti, F, Higuchi, T, Otani, F, Ripp-Baudot, I, Nakamura, K R, Rehman, J U, Bacher, S, Dujany, G, Irmler, C, Mohanty, G B, Gautam, V, Friedl, M, Libby, J, Baudot, J, Wang, S J, Bosisio, L, Das, S B, Wiechczynski, J, Ishikawa, A, Kaleta, M, Paladino, A, Cheshta, C, Gobbo, B, Lalwani, K, Amos, K, Wang, Z, Schwanda, C, Zani, L, Natkaniec, Z, Uematsu, Y, Casarosa, G, Ravindran, K, Vitale, L, Raj, V, Rizzo, G, Hara, K, Kumar, R, Massaccesi, L, Kang, K H, Adamczyk, K

2025

Overview

The silicon strip sensors of the Belle II silicon vertex detector were irradiated with 90 MeV electron beams up to an equivalent 1-MeV-neutron fluence of \\(3.0\\times 10^{13}~{\\rm n}_{\\rm eq}/{\\rm cm^2}\\). We measure changes in sensor properties induced by radiation damage in the semiconductor bulk. Electrons around this energy are a major source of beam-induced background during Belle II operation. We discuss observed changes in full depletion voltage, sensor leakage current, noise, and charge collection. The sensor bulk type inverts at an equivalent 1-MeV-neutron fluence of \\(6.0\\times 10^{12}~{\\rm n}_{\\rm eq}/{\\rm cm^2}\\). The leakage current increases proportionally to the radiation dose. We determine a damage constant of \\(3.9 \\times 10^{-17}\\) A/cm at 17 C\\(^\\circ\\) immediately after irradiation, which drops significantly to approximately 40% of the initial value in 200 hours, then stabilizes to approximately 30% of the initial value in 1000 hours. We measure sensor noise and signal charge for a sensor irradiated with the equivalent 1-MeV-neutron fluence of \\(3.0\\times 10^{13}~{\\rm n}_{\\rm eq}/{\\rm cm^2}\\). Noise increases by approximately 44% after irradiation, while signal charge does not change significantly when a sufficiently high bias voltage is applied.

• Publisher: Cornell University Library, arXiv.org
• Subject: Electric potential / Electron beams / Electron irradiation / Equivalence / Fluence / Leakage current / Noise measurement / Radiation / Radiation damage / Radiation dosage / Sensors / Silicon / Strip / Voltage