THE ESTIMATION FOR ERRORS OF A PLANAR XY STAGE FROM PROFILES MEASUREMENT OF GUIDE-WAYS

摘要

A planar XY stage is frequently used as a precision positioning system for equipment producing semiconductors or flat panel display. Therefore, higher velocities and better accuracies are required to reach higher productivity and performance measures. A planar XY stage, for which an H-shaped frame is usually used as a base stage, is driven by two actuators, such as linear motors, with two position feedback sensors, such as linear scales or interferometers on the scanning motion axis. The stage is frequently used as main frame of the equipment. Therefore the machining and assembly process of rail and bed of the stage is one of first process during the equipment is built. The 2D position error, motion error and flatness of the stage can be measured when the real test is performed. If the errors of stage didn't meet the requirement of it's specification, the stage must be corrected for machining and assembly process again. It is difficult and time consuming work, if assemble and disassemble process is repeated for such a big stage. In this paper, the estimation method for errors of a planar XY stage is suggested, which is applied during the rails and bed of stage is evaluated. To estimate the errors of a planar XY stage, profiles measurement, estimation of motion error and 2D position estimation model is used.