Study of the vibrational modes of subsurface oxygen on Al (111) using diode laser infrared reflection-absorption spectroscopy
Abstract
Infrared reflection absorption spectroscopy (IRRAS), using polarization modulation and tunable diode laser excitation, has been applied to the study of the vibrational modes of subsurface oxygen on Al (111). The dependence of the spectra on O2 exposure and on annealing has been investigated at a resolution of about 10 to 20 cm (1.2 to 2.5 meV) and correlated with Auger data. The absorption band (780 to 920 cm) consists of overlapping bands at about 835 and 862 cm associated, respectively, with isolated sites and with clusters of such sites resembling Al2O3. The apparent shift of this band to higher energy with increasing coverage, observed at lower resolution (but higher sensitivity) in electron energy loss spectroscopy, is found to result from the change in relative intensity of the two modes.
- Publication:
-
Naval Research Lab. Report
- Pub Date:
- October 1987
- Bibcode:
- 1987nrl..reptT....B
- Keywords:
-
- Absorption Spectra;
- Aluminum;
- Diodes;
- Infrared Spectroscopy;
- Laser Spectroscopy;
- Oxygen;
- Vibration;
- Annealing;
- Electron Energy;
- Electron Spectroscopy;
- Energy Bands;
- Semiconductor Lasers;
- Spectral Bands;
- Tunable Lasers;
- Lasers and Masers