Influence of H on the composition and atomic concentrations of "N-rich" plasma deposited SiOxNyHz films
The influence of H on the composition and atomic concentrations of Si, O, and N of plasma deposited SiOxNyHz films was investigated. The bonding scheme of H was analyzed by Fourier-transform infrared spectroscopy. The composition and absolute concentrations of all the species present in the SiOxNyHz...
| Autores: | , , , |
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| Tipo de recurso: | artículo |
| Fecha de publicación: | 2004 |
| País: | España |
| Institución: | Universidad Complutense de Madrid (UCM) |
| Repositorio: | Docta Complutense |
| Idioma: | inglés |
| OAI Identifier: | oai:docta.ucm.es:20.500.14352/51120 |
| Acceso en línea: | https://hdl.handle.net/20.500.14352/51120 |
| Access Level: | acceso abierto |
| Palabra clave: | 537 Silicon-Oxynitride Films Chemical-Vapor-Deposition Electron-Cyclotron-Resonance Tetrahedron Model Thin-Films vibrations Oxide CVD. Electricidad Electrónica (Física) 2202.03 Electricidad |
| Sumario: | The influence of H on the composition and atomic concentrations of Si, O, and N of plasma deposited SiOxNyHz films was investigated. The bonding scheme of H was analyzed by Fourier-transform infrared spectroscopy. The composition and absolute concentrations of all the species present in the SiOxNyHz, including H, was measured by heavy-ion elastic recoil detection analysis (HI-ERDA). Samples were deposited from SiH4, O-2, and N-2 gas mixtures, with different gas flow ratios in order to obtain compositions ranging from SiNyHz to SiO2. Those samples deposited at higher SiH4 partial pressures show both Si-H and N-H bonds, while those deposited at lower SiH4 partial pressures show N-H bonds only. The Si-H and N-H bond concentrations were found to be proportional to the N concentration. The concentration of H was evaluated from the Si-H and N-H stretching absorption bands and compared to the HI-ERDA results, finding good agreement between both measurements. The deviation from H-free stoichiometric SiOxNy composition due to the presence of N-H bonds results in an effective coordination number of N to produce Si-N bonds lower than 3. By fitting the experimental composition data to a theoretical model taking into account the influence of N-H bonds, the actual concentration of N-H bonds was obtained, making evident the presence of nonbonded H. The presence of Si-H and Si-Si bonds was found to partially compensate the effect of N-H bonds, from the point of view of the relative N and Si contents. Finally, the presence of N-H bonds results in a lower Si atom concentration with respect to the stoichiometric film, due to a replacement of Si atoms by H atoms. This decrease of the Si concentration is lower in those films containing Si-H and Si-Si bonds. A model was developed to calculate the Si, O, and N atom concentrations taking into account the influence of N-H, Si-H, and Si-Si bonds, and was found to be in perfect agreement with the experimental data measured by HI-ERDA. |
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