Coupled effects of electronic and nuclear energy deposition on damage accumulation in ion-irradiated SiC

Abstract

Coupling between electronic and nuclear energy dissipation in ion-irradiated, single crystal 4H-SiC has been investigated using Si, Ti, and Ni ions over a range of energies at 300 K, and irradiation damage accumulation is characterized using Rutherford backscattering spectroscopy in channeling geometry. The damage production rate from nuclear energy loss (Sn) is observed to decrease with increasing electronic energy loss (Se) of the incident ions. A dynamic threshold (Se,th) in electronic energy loss is determined for each ion species, which defines two regions: i) Se > Se,th, where electronic energy dissipation fully suppresses damage production due to nuclear energy loss along incident ion paths, and ii) Se < Se,th, where simultaneous damage recovery due to Se competes with damage production processes. The electronic energy loss threshold (Se,th) increases sublinearly with incident ion atomic number. The assessment of Se,th and how it affects damage accumulation is important to advance the understanding of complex processes occurring under ion-solid interactions, as well as in the design of functional materials for opto-electronics and novel structural materials and devices tolerant to harsh thermal and radiation environments.