Effects of high-temperature annealing on electron spin resonance in SiO x films prepared by R. F. sputtering system

• Published in: Journal of non-crystalline solids 2011-02, Vol.357 (3), p.981-985
• Main Authors: Shamekh, A.M.A., Tokuda, N., Inokuma, T.
• Format: Article
• Language: English
• Subjects: Annealing; Bonding; Electron paramagnetic resonance; Electron spin resonance; ESR; Mathematical models; Silicon; Silicon dioxide; Silicon suboxide; Spectra; Structure
• ISSN: 0022-3093; 1873-4812
• DOI: 10.1016/j.jnoncrysol.2010.10.045

Electron spin resonance (ESR) spectra are investigated in order to analyze paramagnetic defects in amorphous SiO x films with 0.8 ≤ x ≤ 1.87 prepared by a co-sputtering of Si-wafer chips and a SiO 2 disk target. Effects of the thermal annealing at 900 °C and 1100 °C on the ESR spectra are also investigated. Four types of silicon dangling bond centers with forms of •Si ≡ Si 3 − n O n ( n = 0, 1, 2 or 3) are assumed in order to simulate the ESR spectra. The random bonding model appears to describe the network structure of the films with x ~ 2, that is, near the stochiometric composition of SiO 2. It is suggested that the structural fluctuation around silicon dangling bonds is larger in the sputtered SiO x films used in the present work in comparison with those prepared by plasma-enhanced chemical vapor deposition. ►The ESR spectra of as-deposited SiO x films depend on x. ►SiO x film structure follows RMM over a compositional range of x = 1.1–1.8. ►The ESR spectra are also affected by thermal annealing. ►Annealed SiO x structure is followed by ESR in connection with PL and IR results. ►Substoichiometric SiO x suffers a thermal decomposition after annealing at 1100 °C.