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arXiv · 2504.18638

Synchrotron light source focused X-ray detection with LGADs, AC-LGADs and TI-LGADs

A. Molnar·Y. Zhao·S. M. Mazza·G. Oregan·M. Davis·S. Beringer·A. Tiernan·J. Ott·H. F. -W. Sadrozinski·A. Seiden·B. Schumm·F. McKinney-Martinez·A. Bisht·M. Centis-Vignali·G. Paternoster·M. Boscardin
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Abstract

The response of Low Gain Avalanche Diodes (LGADs), a type of thin silicon detector with internal gain, to X-rays of energies between 6-16~keV was characterized at the Stanford Synchrotron Radiation Lightsource (SSRL). The utilized beamline at SSRL was 7-2, with a nominal beam size of 30~$\mu$m, repetition rate of 500~MHz, and with an energy dispersion $\Delta E/E$ of $10^{-4}$. Multi-channel LGADs, AC-LGADs, and TI-LGADs of different thicknesses and gain layer configurations from Hamamatsu Photonics (HPK) and Fondazione Bruno Kessler (FBK) were tested. The sensors were read out with a discrete component board and digitized with a fast oscilloscope or a CAEN fast digitizer. The devices' energy response, energy resolution, and time resolution were measured as a function of X-ray energy and position. The charge collection and multiplication mechanism were simulated using TCAD Sentaurus, and the results were compared with the collected data.

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A. Molnar, Y. Zhao, S. M. Mazza, G. Oregan, M. Davis, S. Beringer, A. Tiernan, J. Ott, H. F. -W. Sadrozinski, A. Seiden, B. Schumm, F. McKinney-Martinez, A. Bisht, M. Centis-Vignali, G. Paternoster, M. Boscardin. 2025-04-25. Synchrotron light source focused X-ray detection with LGADs, AC-LGADs and TI-LGADs. https://arxiv.org/abs/2504.18638

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