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Thin PDMS films using long spin times or tert-butyl alcohol as a solvent.

Koschwanez JH, Carlson RH, Meldrum DR - PLoS ONE (2009)

Bottom Line: A better solvent would be one that dissolves uncured PDMS but doesn't swell the underlying substrate.The thickness of the PDMS membranes under different spin speeds, spin times, and PDMS concentrations was measured using an optical profilometer.The use of tert-butyl alcohol to spin thin PDMS films does not swell the underlying PDMS substrate, and we have used these films to construct multilayer PDMS devices.

View Article: PubMed Central - PubMed

Affiliation: Department of Electrical Engineering, University of Washington, Seattle, Washington, United States of America. jkoschwanez@cgr.harvard.edu

ABSTRACT
Thin polydimethylsiloxane (PDMS) films are frequently used in "lab on a chip" devices as flexible membranes. The common solvent used to dilute the PDMS for thin films is hexane, but hexane can swell the underlying PDMS substrate. A better solvent would be one that dissolves uncured PDMS but doesn't swell the underlying substrate. Here, we present protocols and spin curves for two alternatives to hexane dilution: longer spin times and dilution in tert-butyl alcohol. The thickness of the PDMS membranes under different spin speeds, spin times, and PDMS concentrations was measured using an optical profilometer. The use of tert-butyl alcohol to spin thin PDMS films does not swell the underlying PDMS substrate, and we have used these films to construct multilayer PDMS devices.

Show MeSH
Thickness of the PDMS film under various concentrations (by weight) of PDMS in tert-butyl alcohol (TBA) as a function of spin speed.Each data point is the average of the mean thickness of three slides. Each slide was spun for 5 min. The error bar is the 95% confidence interval. The line is the least-squares fit of the data. The density of TBA is 0.775 g/mL at 25°C.
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pone-0004572-g002: Thickness of the PDMS film under various concentrations (by weight) of PDMS in tert-butyl alcohol (TBA) as a function of spin speed.Each data point is the average of the mean thickness of three slides. Each slide was spun for 5 min. The error bar is the 95% confidence interval. The line is the least-squares fit of the data. The density of TBA is 0.775 g/mL at 25°C.

Mentions: Figure 2 shows the PDMS film thickness for different concentrations of PDMS in TBA as a function of spin speed. Each line in Figure 2 is a fit of the data to the generally accepted relationship between angular velocity, ω, and thickness, h [8], [9]:(1)where α and k are the experimentally derived constants shown in Table 2.


Thin PDMS films using long spin times or tert-butyl alcohol as a solvent.

Koschwanez JH, Carlson RH, Meldrum DR - PLoS ONE (2009)

Thickness of the PDMS film under various concentrations (by weight) of PDMS in tert-butyl alcohol (TBA) as a function of spin speed.Each data point is the average of the mean thickness of three slides. Each slide was spun for 5 min. The error bar is the 95% confidence interval. The line is the least-squares fit of the data. The density of TBA is 0.775 g/mL at 25°C.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2642993&req=5

pone-0004572-g002: Thickness of the PDMS film under various concentrations (by weight) of PDMS in tert-butyl alcohol (TBA) as a function of spin speed.Each data point is the average of the mean thickness of three slides. Each slide was spun for 5 min. The error bar is the 95% confidence interval. The line is the least-squares fit of the data. The density of TBA is 0.775 g/mL at 25°C.
Mentions: Figure 2 shows the PDMS film thickness for different concentrations of PDMS in TBA as a function of spin speed. Each line in Figure 2 is a fit of the data to the generally accepted relationship between angular velocity, ω, and thickness, h [8], [9]:(1)where α and k are the experimentally derived constants shown in Table 2.

Bottom Line: A better solvent would be one that dissolves uncured PDMS but doesn't swell the underlying substrate.The thickness of the PDMS membranes under different spin speeds, spin times, and PDMS concentrations was measured using an optical profilometer.The use of tert-butyl alcohol to spin thin PDMS films does not swell the underlying PDMS substrate, and we have used these films to construct multilayer PDMS devices.

View Article: PubMed Central - PubMed

Affiliation: Department of Electrical Engineering, University of Washington, Seattle, Washington, United States of America. jkoschwanez@cgr.harvard.edu

ABSTRACT
Thin polydimethylsiloxane (PDMS) films are frequently used in "lab on a chip" devices as flexible membranes. The common solvent used to dilute the PDMS for thin films is hexane, but hexane can swell the underlying PDMS substrate. A better solvent would be one that dissolves uncured PDMS but doesn't swell the underlying substrate. Here, we present protocols and spin curves for two alternatives to hexane dilution: longer spin times and dilution in tert-butyl alcohol. The thickness of the PDMS membranes under different spin speeds, spin times, and PDMS concentrations was measured using an optical profilometer. The use of tert-butyl alcohol to spin thin PDMS films does not swell the underlying PDMS substrate, and we have used these films to construct multilayer PDMS devices.

Show MeSH