The quality of a precision product, in general, relies on the accuracy and precision of its manufacturing and inspection process. In many cases, the level of precision in the manufacturing and inspection system is also dependent on the positioning capability of tool with respect to the workpiece in the process. Recently the positioning accuracy level employed for some of precision product has reached the level of submicron and long range of motion is required. For example, for 1GDRM Iithoghrphy, 20nm accuracy and 300mm stroke needs. This paper refers to the lithography stage especially fine stage. In this study, for long stroke and high accuracy, the dual servo system is proposed . For the coarse actuator, LDM(Linear DC Motor)is used and for fine one VCM is used. In this study, we propose the new structure of VCM for the fine actuator. It is 3 axis precision positioning stage for an aligner system. Then we performed the optimal design of the stage to obtain the maximum force which is related to the acceleration of the stage to accomplish throughput of product. To control this fine stage, first, system and parameter modelling is performed to correct the modelling error. In this paper, the objects of control are resolution and high speed. To attain it, gain scheduling control method based on the TDC(Time Delay Control) is applied in control step. Reference model gain of TDC is varied according to the real time state in the system control process. By this method high gain control which made the system have high disturbance rejection ability can be performed in the fine error region. And low gain control considering the actuator saturation limit to prevent wind up phenomena is performed in large error region. As a result we could control the actuator to have the resolution below 50nm which is the resolution that wafer needs.
