The (0001)-surface of 6HSiC: morphology, composition and structure

• Published in: Applied surface science Vol. 89; no. 2; pp. 175 - 185
• Main Authors: Starke, U., Bram, Ch, Steiner, P.-R., Hartner, W., Hammer, L., Heinz, K., Müller, K.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01-06-1995; Elsevier Science
• Subjects: Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Materials science; Physics; Solid surfaces and solid-solid interfaces; Surface structure and topography; Surface treatments; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Dangling bonds; Wet process; Inorganic compounds; Superstructure; Silicon carbides; Oxidation; Crystal faces; Step; Chemical etching; Experimental study; STM; Surface structure
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/0169-4332(95)00024-0

The morphology, composition and structure of wet chemically prepared 6HSiC(0001) samples were investigated immediately after introduction into vacuum. Scanning tunneling microscopy displayed large atomically flat areas on the surface. The step structure found is correlated to the sample periodicity normal to the surface. Most step heights are multiples of half the vertical unit cell length. Low-energy electron diffraction (LEED) revealed good surface order with bulk-like lateral periodicity. From high-resolution electron energy loss spectroscopy the saturation of dangling bonds with hydroxyl species could be determined. This termination is responsible for an electron beam sensitivity found in LEED. Upon annealing the oxygen is removed and carbon-carbon bonds develop on the surface as demonstrated by Auger electron spectroscopy. This new structure is ordered in a (√3 × √3)R30° periodicity.