Effect of inelastic ion collisions on low-gain avalanche detectors explained by an A_Si-Si_i-defect mode

Kevin Lauer; Stephanie Reiß; Aaron Flötotto; Katharina Peh; Dominik Bratek; Robin Müller; Dirk Schulze; Wichard Beenken; Erik Hiller; Thomas Ortlepp; Stefan Krischok

arXiv · 2311.07280

Effect of inelastic ion collisions on low-gain avalanche detectors explained by an A_Si-Si_i-defect mode

Kevin Lauer·Stephanie Reiß·Aaron Flötotto·Katharina Peh·Dominik Bratek·Robin Müller·Dirk Schulze·Wichard Beenken·Erik Hiller·Thomas Ortlepp·Stefan Krischok

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Abstract

The acceptor removal phenomenon (ARP), which hampers the functionality of low-gain avalanche detectors (LGAD), is discussed in frame of the A_Si-Si_i-defect model. The assumption of fast diffusion of interstitial silicon is shown to be superfluous for the explanation of the B_Si-Si_i-defect formation under irradiation, particular at very low temperatures. The experimentally observed properties of the ARP are explained by the donor properties of the B_Si-Si_i-defect in its ground state. Additionally, low temperature photoluminescence spectra are reported for quenched boron doped silicon showing so far unidentified PL lines, which change due to well-known light-induced degradation (LID) treatments.

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Kevin Lauer, Stephanie Reiß, Aaron Flötotto, Katharina Peh, Dominik Bratek, Robin Müller, Dirk Schulze, Wichard Beenken, Erik Hiller, Thomas Ortlepp, Stefan Krischok. 2023-11-13. Effect of inelastic ion collisions on low-gain avalanche detectors explained by an A_Si-Si_i-defect mode. https://arxiv.org/abs/2311.07280

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