Influence of steps and defects on the dissociative adsorption of molecular hydrogen on silicon surfaces
|Reviews and Highlights||Quantum Science||Molecular and Soft-matter||Ultrafast Nano-optics and Nanophotonics||Mineralogy and Geochemistry|
M.B. Raschke, U. Höfer
Applied Physics B: Lasers & Optics 68 (3)
The dissociative adsorption of molecular hydrogen on vicinal Si(001) and Si(111) surfaces was investigated by means of optical second-harmonic generation (SHG). For temperatures up to 600 K the measured initial sticking coefficients could be decomposed into contributions from step/defect and terrace sites. Whereas the presence of steps on Si(111) leads only to a moderate increase of reactivity, the sticking coefficients for step adsorption on misoriented Si(001) are many orders of magnitude higher than for terrace adsorption and reach values up to 10−4. Neither the absolute values nor the temperature dependence of adsorption on the terraces are affected by the misorientation.