Surface Erosion of Ion-Implanted 4H-SiC during Annealing with Carbon Cap
The stability/ erosion of the interface between a C-cap and 4H-SiC have been studied by secondary ion mass spectrometry (SIMS). Aluminum implantation has been used to monitor the position of the moving interface as well as to investigate the influence on the interface stability by the crystal quality of the 4H-SiC. After Al implantation a C-cap has been deposited by pyrolysis of photoresist. Subsequent annealing has been performed at 1900 and 2000 °C with durations between 15 minutes and 1 hour. SIMS measurements have been performed without removal of the C-cap. The surface remains smooth after the heat treatment, but a large amount of SiC material from the uppermost part of the wafer is lost. The amount of lost material is related to for instance annealing temperature, ambient conditions and ion induced crystal damage. This contribution gives a brief account of the processes governing the SiC surface decomposition during C-cap post implant annealing.
Robert Stahlbush, Philip Neudeck, Anup Bhalla, Robert P. Devaty, Michael Dudley and Aivars Lelis
M. K. Linnarsson et al., "Surface Erosion of Ion-Implanted 4H-SiC during Annealing with Carbon Cap", Materials Science Forum, Vol. 924, pp. 373-376, 2018