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Applied Optics

Applied Optics


  • Editor: Joseph N. Mait
  • Vol. 48, Iss. 33 — Nov. 20, 2009
  • pp: 6528–6536

Application of the surface free energy minimization principle to modify the indentation of a polymer mirror structure

Kuo-Yung Hung and Pin-Hsien Wu  »View Author Affiliations

Applied Optics, Vol. 48, Issue 33, pp. 6528-6536 (2009)

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This paper successfully used inclined exposure technology to fabricate 45 ° polymer optical grade micromirrors ( 1.4 mm thick) while applying the surface free energy minimization principle to improve sidewall indentation. This paper tests the effect of the reflow process on the surface roughness of inclined surfaces. Experimental results are considered in light of the theory of minimizing free energy. The smallest surface roughness achieved in the experiments using SU-8 material with a thickness of 1.4 mm was less than 20 nm . The effect of the reflow process on the surface indentation of inclined microstructures showed that the 1D WYKO profile of maximum height fell from 0.81 μm to 0.08 μm ( R t ), which is an improvement of 90% after the reflow process. This type of micromirror can be used as a key component in Blu-Ray optical pickup heads used in portable, high-density storage systems.

© 2009 Optical Society of America

OCIS Codes
(160.5470) Materials : Polymers
(230.3990) Optical devices : Micro-optical devices

ToC Category:
Optical Devices

Original Manuscript: August 10, 2009
Manuscript Accepted: October 21, 2009
Published: November 17, 2009

Kuo-Yung Hung and Pin-Hsien Wu, "Application of the surface free energy minimization principle to modify the indentation of a polymer mirror structure," Appl. Opt. 48, 6528-6536 (2009)

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  23. Partially based on the following paper presented at μTAS 2009 Conference: K. Y. Hung, et al., “Application of the surface free energy minimization principle to improve sidewall indentation of polymer inclined mirrors,” The 13th International Conference on Miniaturized Systems for Chemistry and Life Sciences (μTAS 2009), Jeju Island, Korea, 1-5 November, 2009.

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