Application of Active Micro-vibration Control System using a Giant Magnetostrictive Actuator

In various leading-edge technology areas, such as semiconductor manufacturing, the requirement for micro-vibration control is increasing. The authors have developed an active six-degrees-of-freedom (6-DOF) micro-vibration control system using an off the shelf, giant magnetostrictive (GMS) actuator. The efficiency of the active micro-vibration control system using a GMS actuator has been verified through several control experiments. However, the active micro-vibration control approach has not previously been applied to actual precision measuring equipment. Therefore, the control performance of such systems has not been verified on a practical application. In this study, an active 6-DOF micro-vibration control system using GMS actuators is developed and applied to buildings in order to provide micro-level-vibration-free space for a focused ion beam (FIB). The outline of the system, the design of the control system, and the results of experimental verification are described. In this application of the active micro-vibration control system, the design of the active micro-vibration control system is carried out taking several factors into consideration. Vibration measurements made after adjusting the micro-vibration control system confirm that the table satisfies the specified requirement and that a clear FIB image is obtained under high-magnification observation.