Methods for fabricating high aspect ratio probes and deforming high aspect ratio nanopillars and micropillars

Patent metadata

Field	Value
Publication number	US-9390936-B2
Application number	US-201414527039-A
Country	US
Kind code	B2
Filing date	Oct 29, 2014
Priority date	Feb 25, 2009
Publication date	Jul 12, 2016
Grant date	Jul 12, 2016

Abstract

Methods for fabricating of high aspect ratio probes and deforming micropillars and nanopillars are described. Use of polymers in deforming nanopillars and micropillars is also described.

First claim

The invention claimed is:

1. A method for deforming pillars comprising:
providing a plurality of pillars extending from a substrate, the pillars and the substrate being made of a first material;
partially submerging the pillars in resist made of a second material different from the first material; and
controllably contracting the resist by applying to the resist a radiation cross-linking dose having a value at least ten times that of a standard radiation cross-linking dose for the resist, thereby turning the resist into a negative tone resist;
selectively removing part of the resist; and
controllably and selectively bending the plurality of pillars.

2. The method of claim 1 , wherein the resist is made of Poly methyl methacrylate (PMMA).

3. The method of claim 2 , wherein the applying to the resist a radiation cross-linking dose comprises using an electron-beam.

4. The method of claim 3 , further comprising varying an electron-beam exposure or heating, thereby tuning a force exerted by the PMMA to the plurality of nanopillars.

5. A method for capturing small-scale objects comprising:
providing a plurality of small-scale objects surrounded by a plurality of pillars extending from a substrate, the pillars and the substrate being made of a first material;
partially submerging the pillars in resist made of a second material different from the first material,
controllably contracting the resist by applying to the resist a radiation cross-linking dose having a value at least ten times that of a standard radiation cross-linking dose for the resist, thereby turning the resist into a negative tone resist;
selectively removing part of the resist; and
controllably and selectively bending the plurality of pillars, thereby squeezeing the plurality of small-scale objects and thereby forcing the plurality of small-scale objects through top of the plurality of pillars.

6. The method of claim 5 , wherein the small-scale objects have spherical shapes with diameters of 50 nm or more.

7. The method of claim 5 , wherein the resist is made of poly methyl methacrylate (PMMA).

8. The method of claim 7 , wherein the applying to the resist a radiation cross-linking dose comprises using an electron-beam.

Assignees

• California Inst Of Techn
• Tombrello Stephanie

Inventors

• Henry Michael D
• Homyk Andrew P
• Scherer Axel
• Tombrello Thomas A
• Walavalkar Sameer

Classifications

• H10P50/244

  comprising alternated and repeated etching and passivation steps · CPC title

• H10P50/695

  characterised by the process involved to create the mask, e.g. lift-off masks or sidewalls or to modify the mask · CPC title

• H10P50/692

  characterised by their composition, e.g. multilayer masks or materials · CPC title

• H10P50/242

  of Group IV materials · CPC title

• B81C2201/0159

  Lithographic techniques not provided for in B81C2201/0157 · CPC title