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This study reports the application of the nonresonant type ultrasonic motor (NRUSM) to a 300 mmstroke ultra-precision stage for the future nanoelectronics manufacturing. The advantages of the NRUSM are high resolution and no magnetic noise generation due to the DC characteristics of the piezoelectric device, and high servo rigidity and no additional brake mechanism needed due to direct drive mechanism. It is confirmed that the NRUSM is suitable for ultra-precision positioning, slow and high velocity feeding at closed-loop control. The NRUSM driven stage performance results are; (1) maximum velocity 50 mm/s over the 300 mm-stroke at open-loop control;( 2 ) positioning accuracy of k0.69 nm at step and repeat response, and position accuracy at constant velocity feeding 10 nm/s -36 mm/s below 20 nm at closed-loop control.

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A new wear reduction method, which is based on a static friction without slipping, is developed for a frictionally fast feeding piezoactuator. This method is required for overcoming the problems related to the scattering of particles due to the use of a contact type actuator. Furthermore, wear reduction result in a frictionally driving actuator with a long-term stability for various applications, such as the electron beam inspection in the next-generation semiconductor industry.