Fabrication of 4H-SiC Low Gain Avalanche Detectors (LGADs)

Abstract:

Low gain avalanche detectors (LGADs) offer high temporal resolution for high energy particle detection, which is critical for next generation experiments in hadron colliders. While silicon LGADs (Si-LGADs) have rapidly matured in the last decade, research into silicon carbide (SiC) LGADs has only recently begun. By accounting for fundamental differences in material properties and fabrication processes, we present a prototype device design and process flow for 4H-SiC LGADs with etch-based isolation. Critical steps of the process flow and their results are discussed, including plasma etching, passivation, and the formation of low resistivity contacts. Electrical characterization (I-V, C-V) shows sufficient depletion of the device structure to demonstrate low-gain charge carrier multiplication.

• Periodical: Key Engineering Materials (Volume 1024)
• Pages: 79-86
• DOI: https://doi.org/10.4028/p-0t5ifB
• Online since: September 2025
• Authors: Benjamin J. Sekely, Yashas Satapathy, Tao Yang, Greg Allion, Phillip Barletta, Steve Holland, Stefania Stucci, Carl Haber, Spyridon Pavlidis, John F. Muth*
• Keywords: High Energy Physics, LGAD, Particle Detection, PiN Diode, Radiation

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