| 摘要 |
PURPOSE:To improve the threshold value against an optical damage by forming an ion seed implanted layer and a lithium vacancy layer on the surface of an LiNbO3 crystal substrate or LiTaO3 crystal substrate. CONSTITUTION:An Li vacancy layer 2 is formed by subjecting a lithium niobate LiNbO3 crystal substrate or lithium tantalate LiTaO3 crystal substrate to a high temp. heat treatment and diffusing externally Li2O. An ion seed implanted layer 3 is formed by implanting an ion seed by using an ion exchange method. The layer 2 captures the photoelectron generated by irradiation of light by Li vacancy, thereby preventing the damage of an optical waveguide by photoelectron and improving the threshold value against an optical damage. |
