Method of forming a micro-structure

• US 9,751,755 B2
• Filed: 10/21/2010
• Issued: 09/05/2017
• Est. Priority Date: 10/21/2010
• Status: Active Grant

• Current Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Original Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Inventors: Mardilovich, Peter, Fuller, Anthony M., Wei, Qingqiao
• Primary Examiner(s): Austin, Aaron
• Assistant Examiner(s): Yang, Zheren J
• Application Number:
  US13/825,029
• Publication Number:
  US 20130177738A1
• Time in Patent Office: 2,511 Days
• Field of Search: 977957, 977958, 216 19
• CPC Class Codes: B81B 3/00 Devices comprising flexible or deformable elements, e.g. comprising elastic tongues or membranes B81B5/00 takes precedence
• CPC Class Codes: B81C 1/00031 Regular or irregular arrays of nanoscale structures, e.g. etch mask layer photomechanical, e.g. photolithographic, production of textured or patterned surfaces G03F7/00; lithographic processes for making patterned surfaces using printing and stamping G03F7/0002
• CPC Class Codes: B81C 1/00373 Selective deposition, e.g. printing or microcontact printing
• CPC Class Codes: C25D 1/006 Nanostructures, e.g. using aluminium anodic oxidation templates [AAO]
• CPC Class Codes: C25D 11/022 Anodisation on selected surface areas
• CPC Class Codes: C25D 11/045 for forming AAO templates
• CPC Class Codes: C25D 11/08 containing inorganic acids
• CPC Class Codes: C25D 11/10 containing organic acids
• CPC Class Codes: C25D 11/18 After-treatment, e.g. pore-sealing
• CPC Class Codes: C25D 11/26 of refractory metals or alloys based thereon
• CPC Class Codes: Y10S 977/856 including etching/cutting
• CPC Class Codes: Y10S 977/888 Shaping or removal of materials, e.g. etching
• CPC Class Codes: Y10T 428/24355 Continuous and nonuniform or irregular surface on layer or component [e.g., roofing, etc.]

Abstract

A method of forming a micro-structure involves forming a multi-layered structure including i) an oxidizable material layer on a substrate and ii) another oxidizable material layer on the oxidizable material layer. The oxidizable material layer is formed of an oxidizable material having an expansion coefficient, during oxidation, that is more than 1. The method further involves forming a template, including a plurality of pores, from the other oxidizable material layer, and growing a nano-pillar inside each pore. The nano-pillar has a predefined length that terminates at an end. A portion of the template is selectively removed to form a substantially even plane that is oriented in a position opposed to the substrate. A material is deposited on at least a portion of the plane to form a film layer thereon, and the remaining portion of the template is selectively removed to expose the nano-pillars.

Claims

1. A micro-structure, consisting of:

a substrate;

a non-oxidized portion of an oxidizable material layer formed on the substrate;

an oxide layer formed on the non-oxidized portion and from the oxidizable material layer;

metal oxide nano-pillars extending from the oxide layer and formed from the oxidizable material layer, wherein each of the plurality of nano-pillars has a length that terminates at an end such that the plurality of nano-pillars ends, together, defines a substantially even plane oriented in a position that is opposed to the substrate;

an empty space separating each nano-pillar from each adjacent nano-pillar; and

a film layer formed on at least a portion of the substantially even plane.

2. The micro-structure as defined in claim 1 wherein:

the oxidizable material is chosen from tantalum, tungsten, niobium, and titanium;

the non-oxidized portion of the oxidizable material is tantalum when the oxidizable material is tantalum, tungsten when the oxidizable material is tungsten, niobium when the oxidizable material is niobium, or titanium when the oxidizable material is titanium; and

the oxide layer and the metal oxide nano-pillars are tantalum pentoxide when the oxidizable material is tantalum, tungsten oxide when the oxidizable material is tungsten, niobium oxide when the oxidizable material is niobium, or titanium oxide when the oxidizable material is titanium.

3. The micro-structure as defined in claim 1 wherein each of the plurality of metal oxide nano-pillars includes a pitch ranging from about 30 nm to about 500 nm, a diameter ranging from about 10 nm to about 350 nm, a height ranging from about 10 nm to about 1000 nm, and an aspect ratio that is greater than 10.

4. The micro-structure as defined in claim 1 wherein the film layer-includes a surface modified by a material chosen from aluminum oxide, zirconium oxide, titanium dioxide, silicon dioxide, tungsten oxide, zinc oxide, hafnium oxide, and combinations thereof.

5. The micro-structure as defined in claim 1 wherein the micro-structure includes at least one micro-cluster having a portion of the film layer and a portion of the plurality of metal oxide nano-pillars.

6. The micro-structure as defined in claim 1 wherein the film layer includes at least one opening defined therein.

7. The micro-structure as defined in claim 1 wherein each of the plurality of metal oxide nano-pillars is uniform in at least one of diameter, pitch, or height.

8. The micro-structure as defined in claim 1 wherein the film layer is selected from the group consisting of zinc oxide, aluminum nitride, and lead zirconate titanate.

9. The micro-structure as defined in claim 8, further comprising inter-digitated electrodes formed on the film layer.

10. The micro-structure as defined in claim 1 wherein the substrate is selected from the group consisting of silicon, silicon having an insulating layer thereon, glass, quartz, stainless steel, plastic, and combinations thereof.

11. The micro-structure as defined in claim 1 wherein the nano-pillars comprise an amorphous oxide material.

12. The micro-structure as defined in claim 1 wherein the film layer has a thickness ranging in size from about 10 nm to about 5 μ

m.

13. The micro-structure as defined in claim 1 wherein the film layer has a thickness ranging in size from about 20 nm to about 500 nm.