Raman Spectroscopy Study of Oxygen Vacancies in PbTiO3Thin Films Generated Heat-Treated in Hydrogen Atmosphere

Raman spectroscopy is utilized to study the evaluation of vacancies in PbTiO3 thin films subjected to hydrogen atmosphere heat treatment. The B1 mode consisted of only oxygen ion vibration was shifted to lower frequency with increasing heat treatment temperature. It was considered that the oxygen ions were lacking from PbTiO3, and that oxygen vacancies were generated. It was found that the frequency of the B1 mode is proportional to oxygen ion content. Pb ions were also lacking in the PbTiO3 thin films with oxygen ions and the number of oxygen vacancies was larger than that of Pb ions. We suggest that the Raman spectroscopy is a suitable tool for the evaluation of oxygen vacancies in PbTiO3 thin films.