Abstract
The formation of stable radiation damage in crystalline solids often proceeds via complex dynamic annealing processes, involving migration and interaction of ballistically-generated point defects. The dominant dynamic annealing processes, however, remain unknown even for crystalline Si. Here, we use a pulsed ion beam method to study defect dynamics in Si bombarded in the temperature range from −20 to 140 °C with 500 keV Ar ions. Results reveal a defect relaxation time constant of ~10–0.2 ms, which decreases monotonically with increasing temperature. The dynamic annealing rate shows an Arrhenius dependence with two well-defined activation energies of 73 ± 5 meV and 420 ± 10 meV, below and above 60 °C, respectively. Rate theory modeling, bench-marked against this data, suggests a crucial role of both vacancy and interstitial diffusion, with the dynamic annealing rate limited by the migration and interaction of vacancies.
Highlights
These DA processes are complex and remain poorly understood even for crystalline Si, which is the most extensively studied and arguably best understood material[1]
We use a novel pulsed ion beam technique[7,8,9,10] to measure the T dependence of the DA time constant (τ) in Si bombarded with 500 keV Ar ions in a regime of relatively high ion doses when damage accumulation is dominated by inter-cascade DA processes
This effect is due to the interaction of mobile defects generated in different pulses and, in different cascades
Summary
These DA processes are complex and remain poorly understood even for crystalline Si, which is the most extensively studied and arguably best understood material[1]. Such large inconsistency in the Eas reported (~0.2–1.7 eV) highlights the complexity and currently limited understanding of the fundamental physics governing DA even for Si. Here, we use a novel pulsed ion beam technique[7,8,9,10] to measure the T dependence of the DA time constant (τ) in Si bombarded with 500 keV Ar ions in a regime of relatively high ion doses when damage accumulation is dominated by inter-cascade DA processes (i.e., by the interaction of mobile defects generated in different collision cascades).
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
