Microstamping of freestanding bipolymer features

Applied Physics Letters

Volumn 78, Issue 23, 2001, Pages 3741-3743

  Moran, P M ^a   Robert, C ^b  

^a INSTITUTE OF MATERIALS RESEARCH AND ENGINEERING   (Singapore)

^b NATIONAL UNIVERSITY OF SINGAPORE   (Singapore)

Author keywords

[No Author keywords available]

Indexed keywords

EID: 0039569168     PISSN: 00036951     EISSN: None     Source Type: Journal    
DOI: 10.1063/1.1371784     Document Type: Article

References (13)

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6. B. R. Seckel, Muscle Nerve 13, 785 (1990): A. C. A. Wan, H. Q. Mao, S. Wang, K. W. Leong, L. K. L. L. Ong, and H. Yu, Biomaterials 22, 1147 (2001); C. A. Wan and Hanry Yu (private communications).
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8. 2 (30%-35% aqueous solution). Allied Signal Particle Class sulfuric acid, 95%-97%. Merck VLSI Selectipur hydrogen peroxide, 31%.
9. Octadecyltrichlorosilane, Fluka Chemicals, 90% purity. Perfluorooctyl-trichlorosilane, Fluka Chemicals, 97% purity. Toluene, Merck Chemicals, Analysis Grade, <0.03% water content.
10. R. J. Jackman, D. C. Duffy, E. Ostuni, N. D. Willmore, and G. M. Whitesides, Anal. Chem. 70, 2280 (1998).
11. Generally an ethyl cyanoacrylate based adhesive was used. These adhesives are fast curing and bond well to polymers and glass but do not bond very well to our silanized surfaces.
12. The model is based upon calculating the total interfacial energies of possible equilibrium configurations and selecting the configuration with the minimum energy. We assume a three-dimensional hemispherical droplet passing freely over a cylindrical microwell. The microwell is either not filled at all or is completely filled with liquid that has flat meniscus at the microwell opening regardless of the wetting angle of the liquid on the stamp - this is because the meniscus can be pinned at a sharp edge. Gravity is neglected because the microwells are small. It should be noted that, although neglected in this calculation, dynamic effects might play an important role in certain situations, e.g., when withdrawing a stamp quickly from a beaker of solution.
13. The polyetherimide used was ULTEM 1010R from GE chemicals. The minimum concentration used was 1 g of ULTEM in 30 ml of NMP. In general the concentrations used were many times higher. The NMP was held at 75 °C and stirred until all the ULTEM was dissolved. 12 The cap thickness was estimated by allowing the SEM beam to remain focused on a set of features until the cyanoacrylate became damaged while the ULTEM caps remained unharmed, this made the cap thickness easy to observe.