Low-cost technology for high-density microvalve arrays using polydimethylsiloxane (PDMS)

In this paper, a rapid and low-cost fabrication technology for high-density microvalve arrays is presented. For proof of the concept, a pneumatically-actuated three-way microvalve system composed of three independent one-way valve units was fabricated and tested. Each valve unit has a membrane, which is actuated by external negative air pressure. Intervals between the valve units are smaller than 780 /spl mu/m. These small intervals have been realized by providing the system with a layer of microchannels to conduct the air pressure to the valve units. All the parts were made of inexpensive silicone elastomer - polydimethylsiloxane (PDMS) - and rapidly fabricated with molding and spin-coating. A newly developed technique for wafer level transfer of a PDMS membrane has been proven to be effective. Flow characteristics of the microvalve system for water are presented. The microvalve works in an on-off manner with hysteresis. No leakage has been observed in the closed state. In the open state, measured flow resistances (pressure drops) are within the range of 1.65-2.29 kPa/(/spl mu/L/min).

[1]  E. Delamarche,et al.  Patterned delivery of immunoglobulins to surfaces using microfluidic networks. , 1997, Science.

[2]  T. Fujii,et al.  Droplet-based nano/picoliter mixer using hydrophobic microcapillary vent , 1999, Technical Digest. IEEE International MEMS 99 Conference. Twelfth IEEE International Conference on Micro Electro Mechanical Systems (Cat. No.99CH36291).

[3]  A. Berg,et al.  Micro Total Analysis Systems , 1995 .

[4]  Masayoshi Esashi,et al.  Microflow devices and systems , 1994 .

[5]  H. Elderstig,et al.  A Pneumatically Actuated Micro Valve With A Silicone Rubber Membrane For Integration With Fluid-handling Systems , 1995, Proceedings of the International Solid-State Sensors and Actuators Conference - TRANSDUCERS '95.

[6]  A. Manz,et al.  µ-TAS: Miniaturized Total Chemical Analysis Systems , 1995 .

[7]  Chih-Ming Ho,et al.  A MEMS thermopneumatic silicone rubber membrane valve , 1998 .

[8]  S. Shoji,et al.  Three-way microvalve for blood flow control in medical micro total analysis systems (/spl mu/TAS) , 1997, Proceedings IEEE The Tenth Annual International Workshop on Micro Electro Mechanical Systems. An Investigation of Micro Structures, Sensors, Actuators, Machines and Robots.

[9]  G. Whitesides,et al.  Rapid Prototyping of Microfluidic Systems in Poly(dimethylsiloxane). , 1998, Analytical chemistry.

[10]  C. Effenhauser,et al.  Integrated capillary electrophoresis on flexible silicone microdevices:  analysis of DNA restriction fragments and detection of single DNA molecules on microchips. , 1997, Analytical chemistry.

[11]  T. Fujii,et al.  Handling of Picoliter Liquid Samples in a Poly(dimethylsiloxane)-Based Microfluidic Device , 1999 .

[12]  Olivier Thierry Guenat,et al.  High-density arrays of valves and interconnects for liquid switching , 1996 .

[13]  Chang Liu,et al.  Re-configurable fluid circuits by PDMS elastomer micromachining , 1999, Technical Digest. IEEE International MEMS 99 Conference. Twelfth IEEE International Conference on Micro Electro Mechanical Systems (Cat. No.99CH36291).

[14]  G. Whitesides,et al.  Rapid prototyping of microfluidic switches in poly(dimethyl siloxane) and their actuation by electro-osmotic flow , 1999 .

[15]  C. Urbaniczky,et al.  Integrated fluid handling system for biomolecular interaction analysis. , 1991, Analytical chemistry.

[16]  G. Whitesides,et al.  Microfabrication inside capillaries using multiphase laminar flow patterning , 1999, Science.

[17]  Albert van den Berg,et al.  Micro Total Analysis Systems ’98 : Proceedings of the μTAS ’98 Workshop, held in Banff, Canada, 13–16 October 1998 , 1998 .