Direct Determination of Volume Changes in Ion-Beam-Irradiated SiC

A single crystal 6H-SiC wafer was sequentially implanted in two areas at 873 and 295 K using 2.0 MeV Au2+ ions under off-axis conditions. Identical Au profiles, as a function of atomic areal density, were produced at 873 and 295 K. The linear expansion in the amorphous state produced at 295 K was measured relative to the slightly damaged state produced at 873 K, using the Au profiles as references. The red-shift of the plasmon-loss peak was also used to directly measure the local density changes. Based on these measurements, the volume expansion of the amorphous state in 6H-SiC at 295 K is 11.5 ± 1.9%, while that in the slightly damaged state at 873 is 0.9%