Comparative surface studies on wet and dry sacrificial thermal oxidation on silicon carbide

• Published in: Applied surface science Vol. 174; no. 3; pp. 210 - 216
• Main Authors: Koh, A, Kestle, A, Wright, C, Wilks, S.P, Mawby, P.A, Bowen, W.R
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 30.04.2001; Elsevier Science
• Subjects: AFM; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Materials science; Nano-islands; Oxidation; Physics; Sacrificial oxidation; Solid surfaces and solid-solid interfaces; Surface treatments; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); XPS; AFM; XPS; Sacrificial oxidation; Nano-islands; Atomic force microscopy; Inorganic compounds; Semiconductor materials; Dry process; Silicon carbides; Binary compounds; Solid-solid interfaces; Experimental study; Wet process; Silicon oxides; Morphology; Oxidation; X-ray photoelectron spectra
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/S0169-4332(01)00150-7

A comparative study on the effect of wet and dry thermal oxidation on 4H-silicon carbide (SiC) and on sacrificial silicon (Si) thermal oxidation on 4H-SiC surface has been conducted using atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS). The AFM images show the formation of ‘nano-islands’ of varying density on the SiC surface after the removal of thermal oxide using hydrofluoric (HF) acid etch. These nano-islands are resistant to HF acid and have been previously linked to residual carbon [1–3] resulting from the oxidation process. This paper presents the use of a sacrificial silicon oxidation (SSO) step as a form of surface preparation that gives a reproducible clean SiC surface. XPS results show a slight electrical shift in binding energy between the wet and dry thermal oxidation on the standard SiC surface, while the surface produced by the SSO technique shows a minimal shift.