Characterization of LiNbO single-crystal substrates irradiated with electrons

Miyazaki, Hisashi*; Morimoto, Jun*; Toda, Koji*; Onoda, Shinobu; Oshima, Takeshi

Electron irradiation effects on lithium niobate (LiNbO) single crystals have been investigated by photoacoustic spectroscopy (PAS), Fourier transform infrared spectroscopy (FT-IR), and Raman scattering spectroscopy. As a result of PAS and FT-IR, it was found that the oxygen vacancies are generated in LiNbO by electron irradiation. The Raman signal intensity observed from as-sliced surface decreases with increasing electron fluence, although the signal intensity observed from mirror-polished surface is not changed. The differences in these results are related to surface composition. Therefore the control of the composition is the most important to avoid the effects of electron irradiation to LiNbO.