Displacement And Metrology System Esearch For Micro/nano Geometry Measurement By Ultra-violet Optics

As the key technology in the micro-field,nano-positioning technology have been increasingly supported by the hi-tech and scientific research.This dissertation provided a 2-DOF nano-positioning stage using the flexure-based mechanism and PZT actuator.The laser interferometer is used to measure the displacement with some optic tweak and support elements.Following is the main work and achievement of this dissertation.1.The analysis of deformation principle and the modeling of the geometric errors of flexure hinge are presented.The dimensionless equation of angular stiffness error considering the geometric errors is derived.The equation can be used for optimized geometric design and performance analysis.2.A 2-DOF nano-positioning stage have been designed with 3 PZT actuators providing a travel of 100?m ×100?M.The operation stiffness,parasitic stiffness and tweak ability is derived by modeling and force analysis.The FEA is presented which showed similar results when compared with theory analysis and verifying the correctness of the formulation derived and the design method.3.A three axis measurement system is designed to measure the linear movement of X and Y axis in addition of angular measurement of Z axis.The theoretical resolution is 0.15nm.Another two-axis and 5-DOF tweak elements are designed to ensure the operation of laser path.Acording to error analysis,the uncertainty of metrology system is evaluated.4.A small test is conducted with a Zygo interferometer measuring the displacement of P143.03 PZT actuator.And successfully achieved the 6nm,3nm and 2nm step displacement.In order to improve the lab condition some action was taken and the interferometer measurement stability is improved with a ±1.5nm drift.