Scanning spreading resistance microscopy of aluminum implanted 4H–SiC

Results from the application of scanning spreading resistance microscopy (SSRM) for characterization of aluminum implanted 4H–SiC are presented. The implanted profiles are investigated electrically and morphologically as a function of post-implantation anneal conditions. The method is shown to be advantageous for measuring and optimizing the activation in many aspects with respect to existing alternative techniques: it provides information of the entire depth and Al concentration range, it is unaffected by annealing induced re-growth and/or surface roughening, and requires little sample preparation. The results indicate that the apparent activation and surface roughness do not saturate in the investigated temperature range of 1500–1650 °C. Finally, an apparent activation energy for the process of 3 eV is estimated.