OPTICAL WAVEGUIDE DEVICE OF LINBO3 THIN FILM AND PRODUCTION THEREOF

摘要

PURPOSE: To allow the guiding of only the ordinary light of the short wavelength region light of visible light or the extraordinary light as well with high efficiency by forming the optical waveguide of the LiNbO₃ thin film on an LiNbO₃ substrate by liquid phase epitaxy. ;CONSTITUTION: The optical waveguide 2 of the LiNbO. thin film which is not doped with MgO or is doped with a small quantity of the MgO or is properly doped with ZnO is formed on the LiNbO₃ substrate 1 doped with MgO by liquid phase epitaxy(LPE) using a melt selected to attain about ≥0.985 Li/Nb and about ≤1.04 Li/Nb of the range where good crystallinity is obtainable in such a manner that a refractive index ne attains the refractive index of the substrate 1 or below. The doping quantity of the MgO of the substrate 1 is selected from 0.1 to 10mol%. The LPE of the optical waveguide 2 of the LN thin film is executed by using an Li₂O-₂O₃, flux. An LN substrate layer and the optical waveguide 12 of the LN thin film are successively formed by LPE on the LN substrate and the quantity of the Li in the substrate layer is set larger than in the waveguide 12.;COPYRIGHT: (C)1993,JPO&Japio