Surface Observation of 4H-SiC (0001) Planarized by Catalyst-Referred Etching


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We have developed a novel planarization method called catalyst-referred etching (CARE), which can planarize SiC substrates without the use of an abrasive. In this method, platinum is used as an oxidation catalyst. The surface of CARE-processed 4H-SiC (0001) substrates are atomically flat all over the wafer. It is found that the surface of CARE-processed substrates is composed of alternating wide and narrow terraces with single bilayer-height steps, regardless of the off-cut angle. This unique structure is induced by the differences in the chemical stabilities of the terraces.



Edited by:

W.B. Lee, C.F. Cheung and S. To




S. Sadakuni et al., "Surface Observation of 4H-SiC (0001) Planarized by Catalyst-Referred Etching", Key Engineering Materials, Vol. 516, pp. 452-456, 2012

Online since:

June 2012




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