Mesoscale Machining Capabilities and Issues

Abstract

Mesoscale manufacturing processes are bridging the gap between silicon-based MEMS processes and conventional miniature machining. These processes can fabricate two and three-dimensional parts having micron size features in traditional materials such as stainless steels, rare earth magnets, ceramics, and glass. Mesoscale processes that are currently available include, focused ion beam sputtering, micro-milling, micro-turning, excimer laser ablation, femtosecond laser ablation, and micro electro discharge machining. These mesoscale processes employ subtractive machining technologies (i.e., material removal), unlike LIGA, which is an additive mesoscale process. Mesoscale processes have different material capabilities and machining performance specifications. Machining performance specifications of interest include minimum feature size, feature tolerance, feature location accuracy, surface finish, and material removal rate. Sandia National Laboratories is developing mesoscale electro-mechanical components, which require mesoscale parts that move relative to one another. The mesoscale parts fabricated by subtractive mesoscale manufacturing processes have unique tribology issues because of the variety of materials and the surface conditions produced by the different mesoscale manufacturing processes.