Title
Air-based contactless wafer precision positioning system: Contactless sensing using charge coupled devices
Author
Hooijschuur, R.H.T. (Student TU Delft)
Saikumar, N. (TU Delft Mechatronic Systems Design) 
Hassan HosseinNia, S. (TU Delft Mechatronic Systems Design) 
van Ostayen, R.A.J. (TU Delft Mechatronic Systems Design) 
Date
2022
Abstract
This paper presents the development of a contactless sensing system and the dynamic evaluation of an air-bearing based precision wafer positioning system. The contactless positioning stage is a response to the trend seen in the high-tech industry, where the substrates are becoming thinner and larger to reduce the cost and increase the yield. Using contactless handling it is possible to avoid damage and contamination. The system works by floating the substrate on a thin film of air. A viscous traction force is created on the substrate by steering the airflow. A cascaded control design structure has been implemented to the contactless positioning system, where the Inner Loop Controller (ILC) controls the actuator which steers the airflow and the Outer Loop Controller (OLC) controls the position of the substrate by controlling the reference of the ILC. The dynamics of the ILC are evaluated and optimized for the performance of the positioning of the substrate. The vibration disturbances are also handled by the ILC. The bandwidth of the system has been improved to 300 Hz. For the OLC a linear charge-coupled device has been implemented as a contactless sensor. The performance of the sensing system has been analyzed. During control in steady state, this resulted in a position error of the substrate of 12.9 (Formula presented.) m RMS, which is a little more as two times the resolution. The bandwidth of the OLC is approaching 10 Hz.
Subject
Air-bearing
precision positioning
To reference this document use:
http://resolver.tudelft.nl/uuid:12807df9-62c8-4f0e-943b-1fdea08024d0
DOI
https://doi.org/10.1177/13506501221132104
Embargo date
2023-07-01
ISSN
1350-6501
Source
Institution of Mechanical Engineers. Proceedings. Part J: Journal of Engineering Tribology
Bibliographical note
Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.
Part of collection
Institutional Repository
Document type
journal article
Rights
© 2022 R.H.T. Hooijschuur, N. Saikumar, S. Hassan HosseinNia , R.A.J. van Ostayen