Gain-Layer Project: New Silicon Diode Resource for Studying Radiation Damage in Particle Detector Components
A multinational research collaboration has launched the Gain-Layer Project, producing 19,050 specially engineered silicon diodes to study how radiation degrades the gain layers of Low-Gain Avalanche Diodes (LGADs) used in high-energy particle physics experiments. LGADs are critical detector components, but radiation exposure progressively destroys their gain layers through mechanisms not yet understood at the defect level. Better understanding of this degradation is essential for designing more radiation-hard detectors for future particle physics experiments.
The Gain-Layer Project, a collaboration involving researchers from multiple European institutions, was established to address a fundamental gap in understanding how radiation damages the gain layers of Low-Gain Avalanche Diodes (LGADs), a detector technology widely used in high-energy particle physics. Existing defect spectroscopy techniques such as Thermally Stimulated Currents (TSC) and Deep-Level Transient Spectroscopy (DLTS) are not directly applicable to the highly doped gain-layer material, and prior measurements have only been performed on materials with much lower effective doping concentrations. To bridge this gap, the project fabricated 19,050 diodes from low-resistivity p-type silicon with effective doping concentrations matching those of real LGAD gain layers, incorporating various combinations of Boron, Phosphorus, Oxygen, and Carbon. The paper, updated after peer review, reports initial characterization results from current-voltage (I-V), capacitance-voltage (C-V), Secondary Ion Mass Spectrometry (SIMS), and DLTS measurements on unirradiated diodes. These diodes are intended to serve the broader defect research community for years of ongoing studies into radiation-induced degradation mechanisms. The work represents a foundational infrastructure effort aimed at enabling future irradiation experiments that could ultimately inform the design of more radiation-tolerant detectors for next-generation collider experiments.
What's missing
The paper reports only on unirradiated diodes; results from irradiation studies — the core scientific goal of the project — are not yet available and represent a significant open question.
What different sources said
- arXiv physicsCenter
Gain-Layer Project
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