THIN FILM LITHIUM NIOBATE AND ELECTRO-OPTIC OPTICAL ELEMENTS

摘要

Electro-optic elements (10) are formed in metal oxide films (21), such as lithium niobate, on a substrate such as lithium niobate for utilization in electro-optical devices (10). The electro-optic elements include trenches (22, 23 and 25) in the lithium niobate (11) selected to improve the performance of the device. Travelling wave modulators may be formed with a waveguide having first and second arms (14 et 15), electrodes over the lithium niobate layer, and trenches formed inn the layer to focus the electric field in the waveguide, resulting in improved modulator performance. Lithium niobate films (21) may be deposited on a substrate (11) in an amorphous state that can readily be etched by liquid or dry etchants. The amorphous film may then be converted by annealing to a crystalline form well suited to formation of electro-optical devices (10).