High aspect ratio performance coatings for biological microfluidics

• US 7,879,396 B2
• Filed: 01/31/2005
• Issued: 02/01/2011
• Est. Priority Date: 06/04/2004
• Status: Active Grant

• Current Assignee: SPTS Technologies Limited (KLA Corporation)
• Original Assignee: Applied Microstructures, Inc. (KLA Corporation)
• Inventors: Yi, Richard C., Chinn, Jeffrey D., Nowak, Romuald, Kobrin, Boris
• Primary Examiner(s): Barr; Michael
• Assistant Examiner(s): BOWMAN, ANDREW J
• Application Number:
  US11/048,513
• Publication Number:
  US 20050271810A1
• Time in Patent Office: 2,192 Days
• Field of Search: 422/130, 436/518, 436/43, 436/48, 427/430, 427/458, 427/476, 427/482, 427/523, 427/237, 427/238, 427/239, 427/236, 427/249.1, 427/38, 427/318, 427/255, 427/255.2, 427/255.3, 427/253, 427/279, 427/491, 427/569, 427/576, 427/255.7, 427/575, 298/901.42, 428/36.7
• US Class Current: 427/248.1
• CPC Class Codes: B05D 1/185 applying monomolecular layers B05D1/204 takes precedence
• CPC Class Codes: B05D 1/60 Deposition of organic layers from vapour phase vapour phase deposition in general C23C14/00, C23C16/00
• CPC Class Codes: B05D 2254/04 Applying the material on the interior of the tube
• CPC Class Codes: B05D 5/04 to obtain a surface receptive to ink or other liquid B05D5/02, B41M5/52 take precedence
• CPC Class Codes: B05D 7/22 to internal surfaces, e.g. of tubes
• CPC Class Codes: B05D 7/222 of pipes
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: C23C 16/0227 by cleaning or etching
• CPC Class Codes: C23C 16/045 Coating cavities or hollow spaces, e.g. interior of tubes; Infiltration of porous substrates
• CPC Class Codes: C23C 16/402 Silicon dioxide
• CPC Class Codes: Y10T 29/49432 Nozzle making
• CPC Class Codes: Y10T 428/1383 Vapor or gas barrier, polymer derived from vinyl chloride or vinylidene chloride, or polymer containing a vinyl alcohol unit is sandwiched between layers [continuous layer]
• CPC Class Codes: Y10T 436/11 Automated chemical analysis

Abstract

We have developed an improved vapor-phase deposition method and apparatus for the application of layers and coatings on various substrates. The method and apparatus are useful in the fabrication of biotechnologically functional devices, Bio-MEMS devices, and in the fabrication of microfluidic devices for biological applications. In one important embodiment, oxide coatings providing hydrophilicity or oxide/polyethylene glycol coatings providing hydrophilicity can be deposited by the present method, over the interior surfaces of small wells in a plastic micro-plate in order to increase the hydrophilicity of these wells. Filling these channels with a precise amount of liquid consistently can be very difficult. This prevents a water-based sample from beading up and creating bubbles, so that well can fill accurately and completely, and alleviates spillage into other wells which causes contamination.

Claims

1. A method of improving the ability of a fluid being charged to a conduit to be drawn into and to flow easily within said conduit, wherein an interior surface of said conduit is vapor deposition coated with a material having a hydrophilicity or hydrophobicity which is related to the surface tension of said fluid, said conduit having a tubular structure defining an interior lumen, the conduit being preformed prior to being vapor deposition coated with the material,

wherein said vapor deposited coating includes at least one oxide-based layer and at least one organic functional layer, and

wherein said at least one organic functional layer includes at least one PEG-based layer, where a PEG-based layer provides the upper surface of said coating.

2. A method in accordance with claim 1, wherein said conduit is an opening in the surface of a substrate, and wherein an aspect ratio of a depth of said opening to an equivalent diameter or critical dimension of said opening is greater than 1:

1.

3. A method in accordance with claim 2, wherein said aspect ratio ranges from about 1:

1 to about 10;

1.

4. A method in accordance with claim 1, wherein an aspect ratio of the length of said conduit to an equivalent diameter or critical dimension of said conduit is greater than 1:

1.

5. A method in accordance with claim 1, wherein said fluid is a hydrophilic fluid and said interior surface of said conduit is coated with a coating which increases the hydrophilicity of said interior surface of said conduit.

6. A method in accordance with claim 5, wherein said fluid is a water-based fluid.

7. A method in accordance with claim 1, wherein said vapor deposited coating exhibits a wetting angle ranging from about 5 degrees or less to about 90 degrees.

8. A method in accordance with claim 1, wherein said vapor deposited coating is hydrophilic in nature and exhibits a wetting angle ranging from about 5 degrees or less to about 60 degrees.

9. A method in accordance with claim 1, wherein said vapor deposited coating is hydrophilic in nature and exhibits a wetting angle ranging from about 5 degrees or less to about 45 degrees.

10. A method in accordance with claim 1 or claim 7, wherein said hydrophilic coating is applied over openings in a substrate, wherein said openings have a diameter or an equivalent diameter ranging from about 0.1 mm to about 15 mm.

11. A method in accordance with claim 10, wherein an aspect ratio of a depth of said openings to an equivalent diameter of said opening ranges from about 1:

1 to about 5;

1.

12. A method in accordance with claim 10, wherein said substrate is comprised of a plastic selected from the group consisting of polystyrene, polypropylene, polyethylene, polyvinylchloride, polyimide, polyamide, and acrylic.

13. A method in accordance with claim 2, wherein said aspect ratio is greater than 5:

1.

14. A method in accordance with claim 13, wherein said diameter or critical dimension is less than 1 mm.