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

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 (S_n) is observed to decrease with increasing electronic energy loss (S_e) of the incident ions. A dynamic threshold (S_e,th) in electronic energy loss is determined for each ion species, which defines two regions: i) S_e > S_e,th, where electronic energy dissipation fully suppresses damage production due to nuclear energy loss along incident ion paths, and ii) S_e < S_e,th, where simultaneous damage recovery due to S_e competes with damage production processes. The electronic energy loss threshold (S_e,_th) increases sublinearly with incident ion atomic number. The assessment of S_e,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.