Semiconductor-tool design, disk-drive development, and nanometer-scale metrology require high-resolution positioning stages. Crossed-roller and air-bearing drives can improve resolution, but integration into existing lead screw-driven systems may require many design changes. Now engineers can have the robustness of lead screws on new, sub-nanometer positioning stages, or retrofit a piezo-nut positioner on an acme lead screw.
The piezo nut's active part consists of a stack of ceramic disks, separated by thin, metallic electrodes where the maximum operating voltage is proportional to disk thickness. Patent-pending, the design integrates coarse and fine drives to combine long-travel and micro-fine positioning.
Integrating closed- or open-loop sub-nanometer positioning throughout 10-, 20-, and 30-micron travel ranges results in accuracies of 10 millionths per turn, or 25 millionths per inch.
B. Berj Kafai, Mikrozone
10315 Woodley Ave., Suite 114
Granada Hills, CA 91344
(818) 360-2628. (P)