Continuous wave ultraviolet laser induced frustration of etching in congruent lithium niobate

Summary form only given. Light induced frustration of etching (LIFE) describes the effect of the partial suppression or complete cancellation of chemical etching in the presence of light. We report on the latent frustration of etching which has been observed on the -z face of undoped congruent lithium niobate single crystals induced by prior illumination with a frequency doubled Ar/sup +/ continuous wave laser at 244 nm. It is a latent effect as the laser beam does not have to be present during the etching procedure in HF acid and enables the fabrication of surface relief micron-size features in a simple exposure development manner. Preliminary examination of the etch frustrated area using micro-Raman analysis showed small broadening and shifting of some spectral lines, when compared with the unaffected material, suggesting structural modifications of the surface.