Inter-pad dead regions of irradiated FBK Low Gain Avalanche Detectors

B. Darby; S. M. Mazza; F. McKinney-Martinez; R. Padilla; H. F. -W. Sadrozinski; A. Seiden; B. Schumm; M. Wilder; Y. Zhao; R. Arcidiacono; N. Cartiglia; M. Ferrero; M. Mandurrino; V. Sola; A. Staiano; V. Cindro; G. Kranberger; I. Mandiz; M. Mikuz; M. Zavtranik; M. Boscardin; G. F. Della Betta; F. Ficorella; L. Pancheri; G. Paternoster

doi:10.1088/1748-0221/17/10/c10006

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arXiv · 2111.12656

Inter-pad dead regions of irradiated FBK Low Gain Avalanche Detectors

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Abstract

Low Gain Avalanche Detectors (LGADs) are a type of thin silicon detector with a highly doped gain layer. LGADs manufactured by Fondazione Bruno Kessler (FBK) were tested before and after irradiation with neutrons. In this study, the Inter-pad distances (IPDs), defined as the width of the distances between pads, were measured with a TCT laser system. The response of the laser was tuned using $\beta$-particles from a 90Sr source. These insensitive "dead zones" are created by a protection structure to avoid breakdown, the Junction Termination Extension (JTE), which separates the pads. The effect of neutron radiation damage at \fluence{1.5}{15}, and \fluence{2.5}{15} on IPDs was studied. These distances are compared to the nominal distances given from the vendor, it was found that the higher fluence corresponds to a better matching of the nominal IPD.

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B. Darby, S. M. Mazza, F. McKinney-Martinez, R. Padilla, H. F. -W. Sadrozinski, A. Seiden, B. Schumm, M. Wilder, Y. Zhao, R. Arcidiacono, N. Cartiglia, M. Ferrero, M. Mandurrino, V. Sola, A. Staiano, V. Cindro, G. Kranberger, I. Mandiz, M. Mikuz, M. Zavtranik, M. Boscardin, G. F. Della Betta, F. Ficorella, L. Pancheri, G. Paternoster. 2021-11-24. Inter-pad dead regions of irradiated FBK Low Gain Avalanche Detectors. https://doi.org/10.1088/1748-0221/17/10/c10006

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