17–19 Feb 2026
Palazzo dei Priori, Perugia, Italy
Europe/Rome timezone

Radiation-Tolerance Improvement Studies of the LGAD Gain Layer in HPK Sensors

19 Feb 2026, 14:45
20m
Sala dei Notari (Palazzo dei Priori, Perugia, Italy)

Sala dei Notari

Palazzo dei Priori, Perugia, Italy

Piazza 4 Novembre - PERUGIA ITALY
Oral LGAD LGAD 4

Speaker

Koji Nakamura (KEK High Energy Accelerator Research Organization (JP))

Description

Low-Gain Avalanche Diodes (LGADs) provide excellent timing resolution on the order of 20 ps and are strong candidates for several collider experiments, both as 4D tracking detectors and as timing layers for particle identification. LGADs with capacitively coupled electrodes (AC-LGADs) achieve highly uniform gain and electric fields, enabling fine pixelation without dead regions. These features make AC-LGADs promising devices for future 4D tracking systems. For hadron-collider environments in particular, radiation tolerance remains a key challenge. Higher operating voltages are required to compensate for the removal of active acceptor doping, and single-event burnout (SEB) has been observed when the electric field exceeds roughly 12 V/µm. Improving the radiation tolerance therefore requires reducing the acceptor-removal rate (coefficient CA) in the gain layer. HPK has implemented several mitigation approaches in recent test samples, including carbon co-implantation, compensated acceptor profiles, and reduced oxygen concentration. In this presentation, I will report on the latest results from newly fabricated samples irradiated up to 5×10^15 neq/cm2, together with SEB studies performed using a 70 MeV proton beam.

Author

Koji Nakamura (KEK High Energy Accelerator Research Organization (JP))

Presentation materials