| Lithography technology is the core technology of the semiconductor manufacturing industry. Mainstream and developing lithography machines both adopt the dual-stage technology and the macro-micro positioning technology, while the micro positioning function is achieved by a six degrees of freedom(6-DOF) motion mechanism. The 6-DOF motion mechanism contains a Chuck stage acting as a load-bearing role, a 6-DOF micro motor and the flexural hinges array which can perform connection between the Chuck stage and the 6-DOF micro motor. The motion mechanism can realize nanometer positioning accuracy. Ultra high positioning accuracy puts forward higher requirements on the stage’s dynamic performance. Flexible connection structure in the 6-DOF motion mechanism increases the stage’s compliance, which may significantly harm the dynamic performance of the system.In this dissertation, putting the 6-DOF precision motion mechanism as study object, we mainly focus on the influence of the flexible hinges array on the 6-DOF stage’s dynamic performance and optimizing the shape and distribution of the flexible hinges array to improve the 6-DOF stage’s dynamic performance. Besides, flexible hinges are connected to the Chuck stage through glued joint. The Chuck stage should avoid stress concentration, therefore, stress of the glued joint on the Chuck stage need to be researched. Main contributions of this thesis are the following: 1. Use conic curve to describe and parameterize the notch flexural hinge’s notch shape. Establish the 6-DOF compliance matrix model of the conic type flexural hinge through the Castiglione second theorem. Analysis the influence of notch shape parameters on flexural hinges’ performance indicators, such as compliance, Off-axis/axis compliance ratio and Motion precision. Use finite element analysis software Ansys simulate three translational direction compliance of the flexural hinge, Simulation results show that the errors between theoretical value and simulation result are 1.87%, 4.46% and 5.39%. 2. Establish the multi rigid body model of 6-DOF motion mechanism, and attain the six degrees of freedom compliance matrix model of the system. With maximizing the first natural frequency as the optimization goal, flexural hinges array distribution parameters and flexural hinges shape parameters as optimization parameters, build the optimization models. Optimization Results show that the first natural frequency is 312.83 Hz, Corresponding vibration mode is rotation around x axis. Comparison of optimization results and simulation results, the error between theoretical value and simulation result are 4.17%, and both have the same first vibration mode. 3. Analysis the performance of adhesive joints through finite element analysis. Observation the Stress concentration in two Dimensional analysis model glued surface, Extraction the stress of the interface layer in the 3D model and analysis the effect of three-dimensional effect on the interfacial layer stress. Finite element analysis Glued Models of different bonding layer thickness, layer length, curved shape, Study the influence of layer thickness, layer length, surface layer shape on the stress distribution. 4. Set up experimental system, analysis the modal of 6-DOF motion mechanism and conic type flexural hinge through Hammering method. Based on the Fourier analysis for the input of Hammer impact signal and the output of Accelerometer response signal, Frequency response function of the system is got. Assigned measuring point and get Several Frequency response functions, the fit modals. Comparison theoretical results, simulation results and experimental results of 6-DOF motion mechanism system, the error between theoretical value and experimental result are 7.87%, the error between theoretical value and simulation result are 3.30%, Comparison theoretical results, simulation results and experimental results of the conic type flexural hinge, the error between theoretical value and experimental result are 4.59%, the error between theoretical value and simulation result are 2.44%,In summary, this dissertation proposed a conic type flexural hinge and drive its 6-DOF compliance matrix model, establish the multi rigid body model of Chuck stage, flexural hinges array, Micro motor system, optimized the first natural frequency of system, and research the influence of adhesive joints on the stress distribution on Chuck. |
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