Reduction of Surface Roughness of 4H-SiC by Catalyst-Referred Etching
Flat and well-ordered surfaces of silicon carbide (SiC) substrates are important for electronic devices. Furthermore, researchers have reported that 4H-SiC surface roughness increases by step-bunching during epitaxial growth and annealing. Degradation of device properties induced by surface roughening is of great concern. Therefore, a method to reduce this surface roughening is requested. We have developed a damage-free planarization method called catalyst-referred etching (CARE). In this paper, we planarized 4H-SiC substrates and evaluated the processed surface before and after the epitaxial growth. Then, we reduced the step-bunching on the epi-wafer surface and determined the electrical properties of the Schottky barrier diodes (SBD) on the processed surface.
Anton J. Bauer, Peter Friedrichs, Michael Krieger, Gerhard Pensl, Roland Rupp and Thomas Seyller
T. Okamoto et al., "Reduction of Surface Roughness of 4H-SiC by Catalyst-Referred Etching", Materials Science Forum, Vols. 645-648, pp. 775-778, 2010