MICROSTRUCTURING OF LITHIUM-NIOBATE USING DIFFERENTIAL ETCH-RATE BETWEEN INVERTED AND NON-INVERTED FERROELECTRIC DOMAINS

Single crystal samples of lithium niobate have been spatially patterne d with photoresist, and subsequently domain inverted using electric fi eld poling, to produce a range of two dimensional spatial domain struc tures. Differential etching has subsequently been carried out using mi xtures of hydrofluoric and nitric acids, at a range of temperatures be tween room temperature and the boiling point. The structures produced show very smooth, well defined, deep features, which have a range of a pplications in optical ridge waveguides, alignment structures, V-groov es, and micro-tips. Details are given of the fabrication procedures, a nd examples of structures are shown. (C) 1998 Elsevier Science B.V. Al l rights reserved.