| 摘要 |
PURPOSE:To permit highly efficient modulation or deflection of guided light with low electric power by providing electrodes for modulating or deflecting said light to an untreated part on a crystal substrate where metal is not diffused. CONSTITUTION:After one face of the LiNbO3 crystal 1 is polished, the surface is subjected to ordinary ultrasonic cleaning using methanol, acetone and pure water respectively. Gaseous nitrogen is blown to the substrate to dry the cleaned surface. A mask 11 is provided in tight contact with the point to be manufactured with the comb-shaped electrodes 5, 6 on the cleaned and dried surface of the substrate 1 and a thin Ti film 12 is deposited by evaporation using an electron beam. The substrate 1 is then erected on a holder and is set in a thermal diffusion furnace. The in-furnace temp. is raised from a room temp. and after the specified temp. is attained in the furnace, said temp. is held and in succession, the substrate is moved into the 2nd thermal diffusion furnace. The energization to the 2nd diffusion furnace is stopped and the substrate is allowed to cool down to the room temp. so that the thermally diffused layer 13 of the Ti is formed on the substrate 11. The comb-shaped electrodes 14 are finally formed by using an ordinary photolithography technique. |
