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A technique to chemically etch thin film PLZT has been developed. Micrometer geometries with straight walls have been produced in 0.7 μm thick films. The photolithography procedure was typical of semiconductor type processes. The etching procedure was to agitate the wafers in a solution of one part BOE, two parts HCl, and three parts water, then to dip them in HNO3 diluted 50 %. The etch rate was approximately 0.01 μm/sec. Partial etching is not possible, because the stoichiometry is not maintained during the etch and the surface figure is distorted.

An experiment was performed to establish the possible use of PLZT as an optical data and information storage device by demonstrating its high resolution capabilities. The maximum resolvable resolution obtained in a sample of 7.6/70/30 PLZT with a 4 μm average grain diameter was 140 line pair per millimeter. This translates to a storage density of 5 × 107 bits/in2. The limiting factor of the resolution was found to be the grain diameter. This result suggests that thin film PLZT with average grain diamters of 0.1μm or less are theoretically capable of storing 5000 lp/mm or 6 × 1010 bits/in2.