Vicinal and on-axis surfaces of 6H-SiC(0001) thin films observed by scanning tunneling microscopy
| Autor: | John F. Wendelken, R. Scott Kern, Jun Xu, Satoru Tanaka, Robert F. Davis |
|---|---|
| Rok vydání: | 1996 |
| Předmět: |
Materials science
Annealing (metallurgy) Analytical chemistry Nanotechnology Surfaces and Interfaces Chemical vapor deposition Condensed Matter Physics Surfaces Coatings and Films law.invention law Materials Chemistry Sublimation (phase transition) Wafer Thin film Scanning tunneling microscope Vicinal Molecular beam epitaxy |
| Zdroj: | Surface Science. 350:247-253 |
| ISSN: | 0039-6028 |
| DOI: | 10.1016/0039-6028(95)01105-6 |
| Popis: | Surfaces of 6H-SiC(0001) homoepitaxial layers deposited on vicinal (∼3.5° off (0001) towards [1120]) and on-axis 6HSiC wafers by chemical vapour deposition have been investigated using ultra-high vacuum scanning tunneling microscopy. Undulating step configurations were observed on both the on-axis and the vicinal surfaces. The former surface possessed wider terraces than the latter. Step heights on both surfaces were ∼0.25 nm corresponding to single bilayers containing one Si and one C layer. After annealing at T >1100°C for 3–5 min in UHV, selected terraces contained honeycomb-like regions caused by the transformation to a graphitic surface as a result of Si sublimation. A model of the observed step configuration has been proposed based on the observation of the [2110] or [1210] orientations of the steps and energetic considerations. Additional deposition of very thin (∼2 nm) SiC films on the above samples by gas source molecular beam epitaxy was performed to observe the evolution of the surface structure. Step bunching and growth of 6HSiC layers and formation of 3CSiC islands were observed on the vicinal and the on-axis surfaces, respectively, and controlled by the diffusion lengths of the adatoms. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect