MECHATRONICS AND CONTROL OF A PRECISION MOTION STAGE FOR NANO-MANUFACTURING

High precision motion is critical in the semiconductor industry and as feature size continues to decrease, the need for higher precision increases. This paper presents the control system design and integration of a novel multi-degree of freedom precision stage for nano-manufacturing. It is composed of a 6 DOF wafer holder and a 3 DOF module holder. The modules can be chosen for a desired task, such as a nano-imprint lithography module. Capacitance gauges, interferometers, and photo detectors provide position feedback of the stage. Piezo-electric actuators and linear motors, that produce two orthogonal forces each, produce the desired output. Modeling of the coordinate transformation among the spaces of sensors stage position, and actuators along with dynamic modeling of the stage is presented. Controller design, hardware, and software is described and results comparing simulation and implementation show a closed-loop positioning of less than I nm error in x and y and 0.01 arc seconds in theta(Z) with a sensor noise level of less than 0.2 nm.