Micromachined parylene membrane valve and pump

• US 6,699,394 B2
• Filed: 12/22/2000
• Issued: 03/02/2004
• Est. Priority Date: 11/12/1997
• Status: Expired due to Term

• Current Assignee: California Institute of Technology
• Original Assignee: California Institute of Technology
• Inventors: Yang, Xing, Wang, Xuan-Qi, Grosjean, Charles, Tai, Yu-Chong
• Primary Examiner(s): OLSEN, ALLAN W
• Application Number:
  US09/745,367
• Publication Number:
  US 20010017287A1
• Time in Patent Office: 1,166 Days
• Field of Search: 216/2, 216/39, 216/67, 216/99
• US Class Current: 216/2
• CPC Class Codes: B81B 2201/036 Micropumps
• CPC Class Codes: B81B 2201/054 Microvalves
• CPC Class Codes: B81B 3/0024 Transducers for transforming thermal into mechanical energy or vice versa, e.g. thermal or bimorph actuators electric motors using thermal effects H02N10/00
• CPC Class Codes: F04B 19/24 Pumping by heat expansion of pumped fluid
• CPC Class Codes: F04B 43/043 Micropumps
• 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 2099/0076 using electrical discharge machining [EDM], milling or drilling
• CPC Class Codes: F16K 2099/008 Multi-layer fabrications
• CPC Class Codes: F16K 2099/0094 Micropumps
• 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 99/0015 Diaphragm or membrane valves
• CPC Class Codes: F16K 99/0034 Operating means specially adapted for microvalves
• CPC Class Codes: F16K 99/0036 operated by temperature variations
• CPC Class Codes: F16K 99/0044 using thermo-electric means
• CPC Class Codes: F16K 99/0061 actuated by an expanding gas or liquid volume
• CPC Class Codes: Y10T 137/7737 Thermal responsive
• CPC Class Codes: Y10T 137/7879 Resilient material valve

Abstract

A micromachined fluid handling device having improved properties. The valve is made of reinforced parylene. A heater heats a fluid to expand the fluid. The heater is formed on unsupported silicon nitride to reduce the power. The device can be used to form a valve or a pump. Another embodiment forms a composite silicone/parylene membrane. Another feature uses a valve seat that has concentric grooves for better sealing operation.

Claims

1. A method of forming a composite membrane, comprising:

obtaining a silicon substrate;

opening front and rear windows on said silicon substrate which are adjacent to one another, and have a thinned silicon membrane between them;

forming a layer of thermopneumatically impermeable material on a first side of the substrate;

covering the impermeable material with an elastomeric material on the first side of the substrate; and

removing the thin layer of silicon to leave a free standing material which is a composite of said impermeable material and said elastomeric material.

2. A method as in claim 1 further comprising forming another layer of thermopneumatically impermeable material on a second side of the layer and within the rear side window.

3. A method as in claim 2, wherein said elastomeric forming comprising filling at least a portion of the front side window with a elastomeric material.

4. A method as in claim 3 wherein said elastomeric material is silicone rubber.

5. A method as in claim 4 wherein said impermeable material is Parylene.