Electrostatic valves for microfluidic devices

• US 7,232,109 B2
• Filed: 10/23/2001
• Issued: 06/19/2007
• Est. Priority Date: 11/06/2000
• Status: Expired due to Fees

• Current Assignee: California Institute of Technology
• Original Assignee: California Institute of Technology
• Inventors: Quake, Stephen R., Enzelberger, Markus M., Driggs, B. Scott
• Primary Examiner(s): KEASEL, ERIC S
• Application Number:
  US10/045,132
• Publication Number:
  US 20020109114A1
• Time in Patent Office: 2,065 Days
• Field of Search: 251/129.01
• US Class Current: 251/129.01
• CPC Class Codes: B33Y 80/00 Products made by additive manufacturing
• CPC Class Codes: F15C 5/00 Manufacture of fluid circuit elements; Manufacture of assemblages of such elements integrated circuits
• CPC Class Codes: F16K 2099/0074 using photolithography, e.g. etching
• CPC Class Codes: F16K 2099/0078 using moulding or stamping
• CPC Class Codes: F16K 2099/008 Multi-layer fabrications
• CPC Class Codes: F16K 31/02 electric F16K31/004 takes precedence; magnetic
• CPC Class Codes: F16K 99/0001 Microvalves microdevices B81B1/00; manufacture or treatment of devices or systems in or on a substrate B81C1/00; microfluidic structures B01L3/5027; micropumps F04B19/006
• CPC Class Codes: F16K 99/0011 Gate valves or sliding valves
• CPC Class Codes: F16K 99/0051 using electrostatic means

Abstract

Valve structures formed in elastomer material are electrostatically actuated by applying voltage to a flexible, electrically conductive wire pattern. An actuation force generated between the patterned wire structure and an electrode result in closure of a flow channel formed in elastomer material underlying the wire. In one embodiment of a valve structure in accordance with the present invention, the wire structure is patterned by lithography and etching of a copper/polyimide laminate, with an underlying gold plate positioned on the opposite side of the flow channel serving as an electrode. In an alternative embodiment, a first wire structure is patterned by physically cutting out a first pattern of strips from an Aluminum/Mylar(®) laminate sheet. A second patterned wire structure serving as the electrode is formed by the same method, and positioned on the opposite side of a control channel. Application of an actuation force between the first and second patterned strips closes the control channel and an associated flow channel underlying the control channel.

Claims

1. A valve structure comprising:

a first elastomeric layer defining a flow channel having walls and a deflectable ceiling;

a first electrode positioned on top of the first elastomeric layer over the deflectable ceiling of the flow channel;

a second elastomeric layer positioned over the first electrode;

a third elastomeric layer positioned over the second elastomeric layer, the third elastomeric layer defining a control channel having walls and a ceiling, the second elastomeric layer forming a floor of the control channel; and

a second electrode positioned on top of the third elastomeric layer over the control channel, such that application of a potential difference between the first electrode and the second electrode drives the first electrode and the second electrode together, causing the walls of the control channel and of the underlying flow channel to be driven together.

2. The valve of claim 1 further comprising a reflective micromirror surface positioned over the ceiling of the flow channel, wherein a physical orientation of the reflective micromirror surface altered when the deflectable ceiling of the flow channel is driven into the flow channel.