Research On Macro-micro Fast Coupling System Of Dual-stage

In order to boost the productivity of the lithography, ASML first proposedTwinscan lithography. In Twinscan lithography, two wafer-stages work in parallelbetween measurement position and exposure position, but the problem of wafer-stagesswap has been introduced. Macro-micro fast coupling system of dual-stage is used forthe detachment and coupling of the macro-motion system and the wafer-stage. When themacro-motion system couples with the wafer-stage, the wafer-stage is driven bymacro-motor to achieve long stroke motion. Because the speed and acceleration is verylarge, the coupling system must ensure the safety of the coupling. In order to promotethe productivity, the coupling time should be reduced.Based on the analysis of Macro-micro fast coupling system of dual-stage, thispaper firstly optimizes the design of the clamp coupling mechanism, designs the controlunit, and then conducts systematic analysis when the macro-motion system couples withthe wafer-stage, and finally the experimentally researches have been carried on toverification. Main research contents as following:(1) Based on the analysis of the motion parameters of the wafer-stage and theprinciple of the clamp coupling mechanism, optimize the stroke of the clamp and thepiston, optimize the clamping force of the clamp coupling mechanism, and finally useANSYS to analyze the core unit of the clamp coupling mechanism.(2) Design the pneumatic system, the deflated loop can achieve fast bufferclamping of the clamp coupling mechanism. Simplify the model of the pneumaticsystem and compute the parameters of the pneumatic system. Finally, design the circuitwhich can communicate with the upper computer, control and detect the motion state ofthe clamp coupling mechanism.(3) When the macro-motion system couples with the wafer stage, analyze the airfoot of wafer stage when the driving force of macro motor shifts the center of mass ofwafer-stage in Z direction, and use ANSYS to analyze the X，Y，Z stiffness of thecoupling system.(4) Design the experimental program of clamp motion test and the clamping forcetest. Then, build the motion test platform, exam the stroke of the clamp and theperformance of the pneumatic system. Finally, test the driving force provided by clampcoupling mechanism in X direction whether can satisfy the system requirements.Experiments indicate that: the stroke of the clamp is greater than2mm, which canensure the safety of the coupling process, the opening time and fast buffer closing timeof the clamp coupling mechanism is350ms and850ms respectively. The pneumaticsystem can achieve fast buffer gas which can reduce the mechanical shock of the clamping process. Two clamp coupling mechanism can provide more than1400Ndriving force in X direction, which can ensure the safety of long stroke motion of thewafer stage. Macro-micro fast coupling system of dual-stage can meet the engineeringrequirements.