Contactless magnetically levitated silicon wafer transport system

Department of Mechatronics, Kwangju Institute of Science and Technology, 572 Sangam-dong, Kwangsan-ku, Kwangju 506-303, Korea; Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology, 373-1, Kusong-dong, Yusong-gu, Taejon 305-701, Korea; Plasma Material Technology, 9255 Dering Avenue, Chatsworth, CA 91311, U.S.A.
Mechatronics (Impact Factor: 1.82). 08/1996; 6(5). DOI: 10.1016/0957-4158(95)00083-6

ABSTRACT A new magnetically levitated wafer transport system is developed for the semiconductor fabrication process to get rid of the particle and oil contaminations that normally exist in conventional transport systems. The transport system consists of levitation, stabilization tracks, and a propelling system. Stabilities needed for levitation in the transport system are achieved by an antagonistic property produced in the tracks and using a simple feedback control. The continuous propelling force is obtained by sending specific current patterns to the propulsion coils. The dynamic model of the transport system is presented and analyzed.

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