An ultrafast thermal spike within a time interval of a few pico-seconds generated by intense ionizing energy deposited using 100 MeV Ag ions is utilized to study the atomistic details of damage recovery in 4H-SiC. Sequential single ion irradiations were performed using 300 keV Ar and 100 MeV Ag in ⟨ 0001 ⟩ 4H-SiC to invoke swift heavy ion (SHI) beam induced epitaxial recrystallization in samples with different degrees of pre-damaged conditions. SHI irradiation was carried out at both room temperature and a low temperature of ∼ 80 K. Low-temperature irradiation was carried out to arrest thermal diffusion of defects and to isolate ionization-induced defect migration in 4H-SiC. Insights into the thermal spike generated by ionizing events in crystalline and amorphous regions at both the temperatures predict a SiC response to SHI. The results emphasize the role of different degrees of pre-damage induced physico-chemical conditions and irradiation temperatures against SHI-induced recrystallization as evaluated by Rutherford backscattering/channeling, Raman spectroscopy, and hard x-ray photoelectron spectroscopy. Understanding the dependence of ion-beam damage accumulation and their recovery on the inelastic to elastic energy loss ratio is important for the performance prediction of SiC intended for extreme environments such as space, defense, and nuclear radiation. We report substantial damage recovery even at a near liquid nitrogen temperature of ∼ 80 K. The recovery gets impeded mainly by the formation of complex defects having homonuclear bonds. The results are explained in the framework of the inelastic thermal spike model, and the role of phonon in the damage recovery process is emphasized.

中文翻译：

---

4H-SiC 中强烈电离辐射诱导的原子向再结晶运动

使用 100 MeV Ag 离子沉积的强电离能量在几皮秒的时间间隔内产生超快热尖峰，用于研究 4H-SiC 损伤恢复的原子细节。在 ⟨ 0001 ⟩ 4H-SiC 中使用 300 keV Ar 和 100 MeV Ag 进行连续单离子照射，以在具有不同程度预损伤条件的样品中调用快速重离子 (SHI) 束诱导外延再结晶。SHI 辐照在室温和约 80 K 的低温下进行。低温辐照用于阻止缺陷的热扩散并隔离 4H-SiC 中的电离诱导的缺陷迁移。对两种温度下结晶区和非晶区电离事件产生的热尖峰的洞察预测了 SiC 对 SHI 的响应。结果强调了不同程度的预损伤诱导的物理化学条件和辐照温度对 SHI 诱导的再结晶的作用，如卢瑟福背散射/沟道效应、拉曼光谱和硬 X 射线光电子能谱所评估的。了解离子束损伤累积及其恢复对非弹性与弹性能量损失比的依赖性对于用于极端环境（如太空、国防和核辐射）的 SiC 的性能预测非常重要。我们报告了即使在接近 80 K 的液氮温度下也能获得大量损伤恢复。恢复主要受到具有同核键的复杂缺陷的形成的阻碍。结果在非弹性热尖峰模型的框架中得到解释，