Effect of Hydrogenation on Defect Reactions in Silicon Particle Detectors

Abstract

The influence of preliminary treatment in hydrogen plasma on elimination of radiation defects and formation of thermal donors has been studied in detector structures made of standard and oxygenated float zone silicon has been studied. A new type of thermal donors has been found in as-treated diodes. These thermal donors are unstable and can be eliminated by heat-treatment at 200-250°C. After irradiation with 3.5 MeV electrons the detectors had been annealed at temperatures of 50-350 °C. It has been found that preliminary hydrogenation at 300 °C leads to disappearance of main vacancy-type radiation defects at lower annealing temperatures. The annealing of hydrogenated and irradiated crystals is accompanied by hydrogen redistribution and formation of hydrogen-related donors. Preliminary irradiation influences on both these processes.

Recent advancements in the development of radiation hard semiconductor detectors for S-LHC

“…It is expected that an enrichment with hydrogen will lead to more radiation-tolerant devices due to hydrogen passivation of radiationinduced defects [28,29], and acceleration of oxygen diffusion by promoting the formation of oxygen dimmers O 2 [30][31][32]. In a first experiment standard FZ devices were hydrogenated in a plasma at 300 1C for 2 h, irradiated with 3.5 MeV electrons to a dose of 3 Â 10 12 cm À2 followed by an isochronal annealing for 30 min up to 350 1C in steps of 50 1C [33]. After each annealing step DLTS spectra and depth profiles of the carrier concentration nðxÞ were recorded.…”