Simulation Of Six Degree-of-freedom Decoupling And Macro Movement Trajectory Planning For Reticle Stage Of Lithography

In the information age，Importance of the LSI manufacturing technology hasbecome increasingly prominent, and the lithography which is a core integratedcircuit manufacturing equipment, its importance is self-evident. wafe stage andreticle stage are the core component of lithography. the controller system controlboth of the stage to do high-speed and high-precision scanning movement, and alsomake the exposure process efficient.This paper mainly studies the reticle stage system. The micro stage of thereticle stage which carries the mask plate could comply scanning movement alongwith the macro stage in a wide range on the one hand, but on the other hand,themicro stage is unconstrained in additional various degrees of freedom in space.sowe should give the system an active control to make the stage meet the designspecifications. In this article we mainly talk about simulation of sixdegree-of-freedom decoupling and macro movement trajectory planning for reticlestage of lithography.Firstly, we discuss function effect and the special mechanical structure of thereticle stage, and come to the conclusion that the micro stage has a couplingrelationship existing in all directions, so we analysis and solve the couplingrelationships from two different aspects, for one aspect we solver it from themotion position relationships of the micro stage,for another aspect we calculate itfrom the relationship between synthesis and decomposition of the force in motion.From both aspect, we get the relationships formulas represented by the matrix.Secondly, we explore the method of designing micro motion control system forthe reticle stage; firstly we establish the virtual prototype of the micro stage inAdams software, set the right environment variables to exchange data with theSimulink software. Based on the two method of decoupling in chapter two, we usetwo kinds of control strategy to design the controller in the Simulink software.Finally we retaliate the joint motion simulation and analysis the simulation results.We obtained that there are some difficulties in the controller system designed basedon decoupling position relationship and the control system designed based onsynthesis and decomposition of the force is more feasible.Then, the article analyzed the method of implement the scanning motion alongy-axis, planned the cubic curve scanning motion path.in order to implement thecontrol system in the engineering prototype, we complete designing the controlsystem software on the hardware circuit. This part of the work is carried out as follows, foremost we Analysis of the overall software structure, after that weintroduce the design in different sub parts. This part include analysis of the reticlecontrol software’s function in PC end,the designing of the multi task embeddedprogram based on VxWorks operating system in VG5board which is the core boardof the reticle system,the logic design of FPGA in the sensor data acquisition board,and also programing of the logic modules and control algorithm in the controlboard.In the experiment section, first we control the macro stage to do a20mm-stepmovement, get performances: step response settling time of16ms, displacementresolution reaches±0.3μm；followed by a dynamic experiments,we achieve thetracking of10Hz sine curve on the stage. then we complete the motion scanningexperiments on the reticle stage system. the performance shows that it’s less than30ms for the stage to move uniformly after the acceleration section, and theposition tracking error is less than10μm when the macro stage is moving with thevelocity of1m/s in the scanning section. It shows that the controller system wedesigned could achieve primary design values of the reticle stage.