PNNL

Abstract

The stopping powers for O, Al, Cr, Mn, Co and Cu in a self-supported SiC film have been measured in transmission geometry over a continuous range of energies using a time of flight elastic recoil detection analysis (ToF-ERDA) system. These stopping data, along with the stopping data in Si and C obtained previously using the same ions and measurement technique, are used to assess the validity of the Bragg additivity rule for stopping powers in SiC over a range of ions and energies. Within the experimental uncertainties (±4%), the results indicate that Bragg's rule is valid in SiC for the ion species and energy region studied. The measured stopping powers in C, Si and SiC are also compared with the stopping power predictions of the two most recent versions of the SRIM (Stopping and Range of Ions in Matter) codes. While both versions of SRIM show varying degrees of agreement with the measured stopping data, there are significant deviations of the SRIM predictions for some ions and energy regions.