Vertical nanopore coupled with a pair of transverse electrodes having a uniform ultrasmall nanogap for dna sequencing

Abstract

A DNA sequencing device, and related method, which include a nanopore having a maximum width dimension of no greater than about 50 nm, and a pair of electrodes having a spacing of no greater than about 2 nm, the electrodes being exposed within the nanopore to measure a DNA strand passing through the nanopore.

What is claimed is: 
     
         1 . A nanopore DNA sequencing device, comprising:
 a nanopore having a maximum width dimension of no greater than about 50 nm;   a pair of electrode members having a spacing of no greater than about 2 nm, the electrodes being exposed within the nanopore to detect an electronic signal associated with one or more nucleotides of a DNA strand passing through the nanopore.   
     
     
         2 . The device of  claim 1 , wherein the nanopore width is no greater than about 50 nm. 
     
     
         3 . The device of  claim 1 , wherein the spacing is no greater than about 1 nm. 
     
     
         4 . The device of  claim 1 , wherein the spacing is in the range of about 0.3 nm to about 2 nm. 
     
     
         5 . The device of  claim 1 , wherein the nanopore is oriented with a vertically upward facing inlet opening. 
     
     
         6 . The device of  claim 1 , wherein the electrode members have a length that is greater than the maximum width dimension of the nanopore. 
     
     
         7 . The device of  claim 1 , wherein the electrode members are formed using a lithography process. 
     
     
         8 . A method of forming a nanopore device for DNA sequencing, the method comprising:
 forming first and second electrode members on a substrate, the first and second electrode members being spaced apart by an electrode gap;   depositing an insulating layer over the first and second electrode members;   forming a nanopore in the insulating layer in alignment with the electrode gap, the nanopore having an inlet opening along a top surface of the insulating layer.   
     
     
         9 . The method of  claim 8 , wherein the electrode gap is in the range of about 0.3 nm to about 2 nm. 
     
     
         10 . The method of  claim 8 , wherein the inlet opening has a minimum width dimension in the range of about 10 nm to about 30 nm. 
     
     
         11 . The method of  claim 8 , wherein forming the first and second electrode members comprises using evaporation techniques. 
     
     
         12 . The method of  claim 8 , further comprising forming the electrode gap by depositing at least one sacrificial layer using at least one of sputter deposition, chemical vapor deposition, and atomic layer deposition, and then removing a portion of the sacrificial layer. 
     
     
         13 . The method of  claim 8 , wherein forming the nanopore includes drilling through the insulating layer using focused electron beam or focused ion beam techniques. 
     
     
         14 . The method of  claim 8 , wherein depositing the insulation coating includes depositing by isotropic deposition. 
     
     
         15 . A method of DNA sequencing, comprising:
 providing a nanopore DNA sequencing device, the nanopore DNA sequencing device comprising a nanopore and a tunneling current electrode, the tunneling current electrode comprising first and second electrode members separated by an electrode gap, the electrode gap being exposed within the nanopore;   directing a DNA strand through the nanopore and the electrode gap;   measuring an electronic signal associated with at least one nucleotide of the DNA strand as the DNA strand passes through the electrode gap.   
     
     
         16 . The method of  claim 17 , wherein the nanopore is oriented with an inlet opening of the nanopore facing vertically upward, and the DNA strand passes through the nanopore and electrode gap in a vertically downward direction. 
     
     
         17 . The method of  claim 17 , wherein a maximum width dimension of the nanopore is no greater than about 50 nm. 
     
     
         18 . The method of  claim 17 , wherein the electrode gap is no greater than about 1 nm. 
     
     
         19 . The method of  claim 17 , wherein the electrode gap is in the range of about 0.3 nm to about 2 nm. 
     
     
         20 . The method of  claim 17 , wherein measuring the electronic signal includes measuring a tunneling current of at least four different nucleotides (A,T,C,G) of the DNA strand.