FERROELECTRIC THIN-FILM PRODUCTION METHOD, VOLTAGE-APPLICATION ETCHING APPARATUS, FERROELECTRIC CRYSTAL THIN-FILM SUBSTRATE, AND FERROELECTRIC CRYSTAL WAFER

摘要

A method for producing a ferroelectric crystal thin film by using a ferroelectric crystal having first and second surfaces opposed to each other and having an etching rate of the first surface higher than that of the second one in a state that the polarization directions are aligned. While applying a predetermined voltage to the ferroelectric crystal, the first surface of the ferroelectric crystal is etched. When the etching progresses and the thickness of the ferroelectric crystal reaches a target value, the directions of polarization of the ferroelectric crystal are inverted and the progress of the enticing automatically stops. Consequently, a ferroelectric crystal thin film extremely thin and uniform in thickness over a wide area can be produced.