Nano-Motion Stage for High-Speed and Precision Positioning on an X-Y Plane

Precision positioning technology with high speed on an X-Y plane which was a coplanar coupling type required a manufacturing inspection for semiconductor and flat display areas, and so on. However, a precise positioning technology with high-speed motion had not been established on the X-Y plane which was coplanar without rotation around a Z axis yet. The authors proposed a new actuator called "Nano-Motion Actuator (NMA)" for track following on a spin-stand that evaluated magnetic heads and media for high density magnetic recording. We applied technologies of the NMA to a new actuator mechanism that had two degrees of freedom called "Nano-Motion Stage (NMS)." A pair of the NMAs was arranged in the directions of the X and Y axes to join two adjacent sides of a floating stage through a pair of parallel links. The floating stage was supported by four directionally elastic springs. As the parallel link changed from a quadrangle to a parallelogram, the floating stage rotation was effectively suppressed by a translational motion. The NMS could be realized a high resonance frequency and a high crossover frequency for its open-loop transfer function. As a result, the position of the NMS could be controlled on the X-Y plane which was coplanar with high speed and subnanometer precision.