The relationship between the Young’s modulus and dry etching rate of polydimethylsiloxane (PDMS)
- 121 Downloads
Polydimethylsiloxane (PDMS) has been the pivotal materials for microfluidic technologies with tremendous amount of lab-on-a-chip devices made of PDMS microchannels. While molding-based soft-lithography approach has been extremely successful in preparing various PDMS constructs, some complex features have to been achieved through more complicated microfabrication techniques that involve dry etching of PDMS. Several recipes have been reported for reactive ion etching (RIE) of PDMS; however, the etch rates present large variations, even for the same etching recipe, which poses challenges in adopting this process for device fabrication. Through systematic characterization of the Young’s modulus of PDMS films and RIE etch rate, we show that the etch rate is closely related to the polymer cross-link density in the PDMS with a higher etch rate for a lower PDMS Young’s modulus. Our results could provide guidance to the fabrication of microfluidic devices involving dry etching of PDMS.
KeywordsPDMS RIE etching Young’s modulus Microfluidic devices
M.F. and D.L. acknowledge a helpful discussion with Dr. Godfrey Saudi. The authors acknowledge the financial support from the National Institutes of Health (Grants Number: 1R21EY026176, 1R01 EY027729), and from National Aeronautics and Space Administration (Grant Number: 80NSSC18K1165), which is a fellowship award to Matthew Fitzgerald under the NASA Space Technology Research Fellowships program.
Compliance with ethical standards
Conflict of interest
The authors declare that they have no conflict of interest.
- D. Armani, C. Liu, N. Aluru, IEEE International MEMS '99 Twelfth IEEE International Conference on Micro Electro Mechanical Systems. (1999)Google Scholar
- D.T. Eddington, W.C. Crone, D.J. Beebe, 7th international conference on miniaturized chemical and Biochem. Analysis Systems (2003)Google Scholar
- M.E. Vlachopoulou, A. Tserepi, N. Vourdas, E. Gogolides, K. Misiakos, J. Phys.: Conference Series. 10, 293 (2005)Google Scholar
- E.J. Wong, Doctoral dissertation. Massachusetts Institute of Technology. (2010)Google Scholar
- R.J. Young, P.A. Lovell, Introduction to Polymers, 2nd edn. (Nelson Thornes, Cheltenham, 2002), p. 310Google Scholar