New technique for fabrication of surface relief Ti-indiffused LiNbO/sub 3/ waveguides

Summary form only given. The variety of optical properties of lithium niobate crystals make this material attractive for many applications such as electro-optic modulators and switches, nonlinear optical frequency converters, optical waveguide amplifiers, lasers and so forth. It is considered as a good candidate for optical integrated circuits since both passive and active components can be combined on the same chip. For the previously stated reasons, surface patterning of lithium niobate crystals can be very useful for many applications such as Bragg reflectors, gain flattening filters etc. Several techniques have been proposed for the fabrication of such structures but they either are very complicated or of limited quality and not easily controllable since they are based on direct laser ablation alone. The method proposed combines surface damage produced by an excimer laser followed by wet etching. The acid preferentially attacks the laser modified areas and the depth of the pattern is controllable via the etching time.