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arXiv · 2207.07355

Optimization of capacitive coupled Low Gain Avalanche Diode (AC-LGAD) sensors for precise time and spatial resolution

Sayuka Kita·Koji Nakamura·Tatsuki Ueda·Ikumi Goya·Kazuhiko Hara
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Abstract

Capacitive-coupled Low-Gain Avalanche Diode (AC-LGAD) sensors are being developed for high-energy particle physics experiments as a detector which provides fast time information with fine spatial resolution. This paper describes optimizations of AC-LGAD sensor fabrication parameters, such as doping concentrations of the gain and electrode layers as well as the AC insulator capacitance, to realize $\mathcal{O}$(10)~\um{} spacial resolution, small charge cross talk to the neighboring electrodes, detection efficiency higher than 99\% at a 10$^{-4}$ fake rate and time resolution of about 30~ps. The radiation tolerance of the sensor is presented. In addition, further application to a device capable of visible and infra-red light detection is discussed.

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Sayuka Kita, Koji Nakamura, Tatsuki Ueda, Ikumi Goya, Kazuhiko Hara. 2022-07-15. Optimization of capacitive coupled Low Gain Avalanche Diode (AC-LGAD) sensors for precise time and spatial resolution. https://doi.org/10.1016/j.nima.2022.168009

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