SC Solutions staff participated in a research and development effort at Delft University of Technology, Netherlands in cooperation with Philips Research Laboratories (Eindhoven, Netherlands) aimed at developing faster and more accurate positioning of wafer stages through advanced control methods. The desired speed requirement is a throughput of 60–80 wafers/hr, and the desired positioning error (accuracy) must not exceed 50 nm with a measurement accuracy of 13 nm.
A new methodology for designing 3-Degree-of-Freedom controllers integrating Feedback control, Feedforward control, and Position-time trajectory design was developed and implemented on a Phillips wafer stepper. The implementation of the advanced control methodology resulted in improvement of state-of-the-art Motion Controllers from Philips: faster settling, and better vibration control.
