| DOI | Resolve DOI: https://doi.org/10.1021/jp0344489 |
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| Author | Search for: Mitchell, S. A.1 |
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| Affiliation | - National Research Council of Canada. NRC Steacie Institute for Molecular Sciences
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| Format | Text, Article |
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| Abstract | Photooxidation of hydrogen-terminated Si(111) surfaces in air has been studied by using optical second harmonic generation (SHG) in reflection from the silicon surface. The mechanism of photooxidation induced by a mercury pen lamp is shown to involve oxygen atoms produced by 185-nm photodissociation of O2 in the gas phase above the Si(111)-H surface. Several fundamental wavelengths were used for SHG, including two-photon resonant excitations that are characteristic of H-terminated and oxidized Si(111) surfaces. By focusing on the anisotropic part of the SHG response, the specific response of intra-bilayer Si-Si bonds was isolated. A pronounced nonmonotonic variation of the SHG signal was observed during photooxidation and also during oxidation of Si(111)-H surfaces in air in the dark. A simple model is described that relates modulations in the SHG signal with progressive oxidation of distinct layers of Si-Si bonds near the surface. An analysis suggests that inter- as well as intra-bilayer bonds are attacked by oxygen atoms at an early stage during photooxidation. |
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| Publication date | 2003-07-23 |
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| In | |
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| Language | English |
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| Peer reviewed | Yes |
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| NPARC number | 12333654 |
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| Export citation | Export as RIS |
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| Report a correction | Report a correction (opens in a new tab) |
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| Record identifier | 21ed5c93-2702-4420-83e7-b68240992964 |
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| Record created | 2009-09-10 |
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| Record modified | 2023-08-11 |
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