Abstract
3C-SiC single crystals have been initially irradiated in the nuclear energy loss regime with 100 keV Fe ions to fluences ranging from 4 × 10 13 to 4 × 1014 cm-2 (i.e. 0.07-0.7 dpa). RBS/C measurements indicate that SiC rapidly becomes amorphous (at ∼0.4 dpa). Two damaged SiC crystals exhibiting a different defective structure have been subsequently irradiated in the electronic energy loss regime with 870 MeV swift heavy (Pb) ions (SHIs) up to a fluence of 4 × 10 13 cm-2. Initially fully amorphous SiC layers showed a decrease in size after SHI irradiation with a recrystallization occurring at the amorphous-crystalline interface. On the contrary, partially amorphous crystals for which onset of amorphization just initiated at the damage peak recovered over the entire damage thickness. Variation of amorphous thickness or disorder level has been monitored as a function of Pb ion fluence, which allowed deriving recrystallization kinetics. Data have been fitted with the direct-impact model and recrystallization cross-sections and threshold values for recovery have been determined for both types of initially defective structures. Differences are qualitatively discussed in terms of nature and density of irradiation defects. All experimental trends have been successfully reproduced by molecular dynamics simulations that mimicked thermal spikes induced by SHIs.
Original language | English |
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Pages (from-to) | 326-331 |
Number of pages | 6 |
Journal | Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms |
Volume | 326 |
DOIs | |
State | Published - May 1 2014 |
Externally published | Yes |
Funding
SHI irradiation experiments have been performed at Grand Accélérateur National d’Ions Lourds (GANIL) Caen, France and were supported by the French Network EMIR. Authors would like to acknowledge M. Toulemonde (CIMAP, Caen, France) for fruitful discussions. AD, LT and FG are grateful to the SEMIRAMIS staff (CSNSM) for their assistance during RBS/C experiments. MB, WJW and OHP were supported by the U.S. Department of Energy, Basic Energy Sciences, Materials Science and Engineering Division. The computational work used the supercomputer resources at the National Energy Research Scientific Computing Center located at Lawrence Berkeley National Laboratory.
Keywords
- Irradiation
- Recrystallization
- SiC
- Swift heavy ion