Hydrophobic valves of plasma deposited octafluorocyclobutane in DRIE channels

被引:76
作者
Andersson, H [1 ]
van der Wijngaart, W [1 ]
Griss, P [1 ]
Niklaus, F [1 ]
Stemme, G [1 ]
机构
[1] Royal Inst Technol, Dept Signals Sensors & Syst, Instrumentat Lab, S-10044 Stockholm, Sweden
关键词
passive valve; liquid control; fluorocarbon; capillary tilling; microfluidics;
D O I
10.1016/S0925-4005(00)00675-4
中图分类号
O65 [分析化学];
学科分类号
070302 ; 081704 ;
摘要
The suitability of using octafluorocyclobutane (C4F8) patches as hydrophobic valves in microfluidic biochemical applications has been shown. A technique has been developed to generate lithographically defined C4F8 hydrophobic patches in deep reactive ion-etched silicon channels. Some of the advantages of this process are that no specific cleaning of the substrate is required, C4F8 is deposited on the sidewalls and the bottom of the channels, a standard photoresist mask can be used to define the patches, and that it is a fast and convenient dry chemical process performed by a standard inductively coupled plasma etcher using the Bosch process. Different patch lengths (200-1000 mum) of C4F8 were deposited in 50 mum wide channels to evaluate which size is most suitable for microfluidic biochemical applications. The valve function of the hydrophobic patches was tested for the following liquids: DD water, acetone, propanol, bead solution and a mixture used for pyrosequencing of DNA. Patch lengths of 200 mum of C4F8 successfully stopped each solution for at least 20 consecutive times. The C4F8 film resists water for at least 5 h. The hydrophobic valve also resists very high concentrations (25%) of surfactants (Tween 80). C4F8 shows a much higher resistance towards water and surface active solutions than previous hydrophobic patches. However, 50% Tween 80 was not stopped at all by the hydrophobic patch. An applied pressure of 760 Pa at the inlet was needed for water to over-run the hydrophobic patch. (C) 2001 Elsevier Science B.V. All rights reserved.
引用
收藏
页码:136 / 141
页数:6
相关论文
共 13 条
[1]  
ANDERSSON H, 2000, IN PRESS SENS ACTU B
[2]   FUNDAMENTALS OF PLASMA POLYMERIZATION [J].
BELL, AT .
JOURNAL OF MACROMOLECULAR SCIENCE-CHEMISTRY, 1976, A 10 (03) :369-381
[3]   Rapid, automated nucleic acid probe assays using silicon microstructures for nucleic acid concentration [J].
Christel, LA ;
Petersen, K ;
McMillan, W ;
Northrup, MA .
JOURNAL OF BIOMECHANICAL ENGINEERING-TRANSACTIONS OF THE ASME, 1999, 121 (01) :22-27
[4]   Microfluidic flow control using selective hydrophobic patterning [J].
Handique, K ;
Gogoi, BP ;
Burke, DT ;
Mastrangelo, CH ;
Burns, MA .
MICROMACHINED DEVICES AND COMPONENTS III, 1997, 3224 :185-195
[5]   Microfabricated capillarity-driven stop valve and sample injector [J].
Man, PF ;
Mastrangelo, CH ;
Burns, MA ;
Burke, DT .
MICRO ELECTRO MECHANICAL SYSTEMS - IEEE ELEVENTH ANNUAL INTERNATIONAL WORKSHOP PROCEEDINGS, 1998, :45-50
[6]  
MATSUMOTO Y, 1999, P TRANSDUCERS 99 S P, P34
[7]  
MCNEELY M, 1999, SPIE, V3877, P210
[8]  
NIKLAUS F, 2000, P EUR S LOW TEMP FUL
[9]  
R BOSCH GMBH, Patent No. 4855017
[10]  
R BOSCH GMBH, Patent No. 4784720