<title>Photofabrication of the third dimension of NiTi shape memory alloy microactuators</title>

Abstract

This paper describes experimental results of using various microlithography techniques to fabricate a range of microactuator devices from NiTi shape memory alloys. The range of products includes: planar double-beams form rolled foils etched form both sides; tapered double-beams; planar double beams from sputter-deposited films etched rom one side; a tubular test piece. Such photofabrication in not easily achieved and problems discussed in this paper include: achieving acceptable edge profiles through the thickness of the materials while maintaining high etch factors; tapering foil microactuators by means of chemical micro milling; coating NiTi tubes with electrophoretic photoresist; imaging a curved surface with a small radius of curvature; control of etching parameters for a constant rate of etch; the influence of NiTi oxide coatings on etching and; technical comparisons with other potential manufacturing processes.