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

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.

1 . A method for fabricating an array of high aspect ratio probes, comprising:
 providing a substrate;   coating the substrate with a first resist;   defining high aspect ratio nanopillars by lithographically patterning the first resist, thus forming a patterned first resist;   developing, with a developer, the patterned first resist to remove portions of the first resist on the substrate, thus forming a developed first resist and exposing portions of the substrate;   depositing an etch mask on the developed first resist and the exposed portions of the substrate to mask the exposed portions of the substrate;   placing the substrate in a chemical bath to dissolve, by way of chemical reactions, the developed first resist and the deposited etch mask on the developed first resist such that the deposited etch mask on the substrate remains undissolved; and   performing an etch with a SF6/C4F8 etch, thus establishing high aspect ratio nanopillars.   
     
     
         2 . The method of  claim 1 , further comprising:
 removing a remainder of the deposited etch mask, thus forming the high aspect ratio nanopillars; and   recoating the substrate with a second resist and selectively removing the second resist to define an exposed portion and a second resist covered portion of the substrate, the exposed portion including at least top regions of the high aspect ratio nanopillars and adapted to define a metal pattern;   depositing a metal layer on both the exposed portion and the second resist covered portion of the substrate; and   lifting off the second resist and the metal layer that is on the second resist covered portion of the substrate, thus leaving behind portions of the metal layer on the exposed portion of the substrate corresponding to the high aspect ratio nanopillars, thus creating metal contacts for the high aspect ratio nanopillars and thereby generating the array of high aspect ratio probes.   
     
     
         3 . A method for fabricating an array of high aspect ratio probes, comprising:
 providing a substrate;   coating the substrate with a first resist;   defining high aspect ratio nanopillars by lithographically patterning the first resist, thus forming a patterned first resist;   developing, with a developer, the patterned first resist to remove portions of the first resist on the substrate, thus forming a developed first resist and exposing portions of the substrate;   depositing an etch mask on the developed first resist and the exposed portions of the substrate to mask the exposed portions of the substrate;   placing the substrate in a chemical bath to dissolve, by way of chemical reactions, the developed first resist and the deposited etch mask on the developed first resist such that the deposited etch mask on the substrate remains undissolved; and   performing an etch with an SF6/C4F8 etch, thus establishing high aspect ratio nanopillars.   
     
     
         4 . The method of  claim 3 , further comprising:
 removing a remainder of the deposited etch mask, thus forming the high aspect ratio nanopillars; and   recoating the substrate with a second resist and selectively removing the second resist to define an exposed portion and a second resist covered portion of the substrate, the exposed portion including at least top regions of the high aspect ratio nanopillars and adapted to define a metal pattern;   depositing a metal layer on both the exposed portion and the second resist covered portion of the substrate; and   lifting off the second resist and the metal layer that is on the second resist covered portion of the substrate, thus leaving behind portions of the metal layer on the exposed portion of the substrate corresponding to the high aspect ratio nanopillars, thus creating metal contacts for the high aspect ratio nanopillars and thereby generating the array of high aspect ratio probes,   wherein the first resist is an electron-beam resist, and the etch mask is an alumina etch mask.   
     
     
         5 . A method for fabricating an array of high aspect ratio probes, comprising:
 providing a substrate;   coating the substrate with a first resist;   defining high aspect ratio nanopillars by lithographically patterning the first resist, thus forming a patterned first resist;   developing, with a developer, the patterned first resist to remove portions of the first resist on the substrate, thus forming a developed first resist and exposing portions of the substrate;   depositing an etch mask on the developed first resist and the exposed portions of the to mask the exposed portions of the substrate;   placing the substrate in a chemical bath to dissolve, by way of chemical reactions, the developed first resist and the deposited etch mask on the developed first resist such that the deposited etch mask on the substrate remains undissolved; and   performing an etch with an SF6/C4F8 etch, thus establishing high aspect ratio nanopillars.   
     
     
         6 . The method of  claim 5 , further comprising:
 removing a remainder of the deposited etch mask, thus forming the high aspect ratio nanopillars; and   recoating the substrate with a second resist and selectively removing the second resist to define an exposed portion and a second resist covered portion of the substrate, the exposed portion including at least top regions of the high aspect ratio nanopillars and adapted to define a metal pattern;   depositing a metal layer on both the exposed portion and the second resist covered portion of the substrate; and   lifting off the second resist and the metal layer that is on the second resist covered portion of the substrate, thus leaving behind portions of the metal layer on the exposed portion of the substrate corresponding to the high aspect ratio nanopillars, thus creating metal contacts for the high aspect ratio nanopillars and thereby generating the array of high aspect ratio probes,   wherein the high aspect ratio nanopillars have diameters ranging from 30 to 50 nm with aspect ratios greater than 25 and the nanopillars are controllably placed within a distance of 50 nm or more from one another.