AVS 56th International Symposium & Exhibition
    Thin Film Wednesday Sessions
       Session TF-WeA

Paper TF-WeA1
ALD Applications to DNA Sequencing, Electrolytic Junctions and Nanofluidics

Wednesday, November 11, 2009, 2:00 pm, Room B4

Session: ALD/CVD: Novel Applications, Mechanical Properties
Presenter: S.M. Rossnagel, IBM T.J. Watson Research Center
Authors: S.M. Rossnagel, IBM T.J. Watson Research Center
S.-W. Nam, IBM T.J. Watson Research Center
Correspondent: Click to Email
One approach to sequencing DNA electrostatically pulls single-stranded DNA through a small, 2-3nm diameter aperture, also known as a nanopore. We have built and configured this electrolytic device with three 3 nm-scale electrodes and nanopores ranging from 15 to 1 nm with the goal of measuring the impedance of each nucleotide (C,G,A,T) as it passes through the nanopore. ALD films are critical to the fabrication at this dimension, and we have focused mostly on dielectric layers where conformality and pinhole-free deposition are critical. A related structure uses an ALD gate dielectric in a single electrode electrolytic device which functions as a pfet at sub 5nm range. (The source and drain are the upper and lower electrolte reservoirs). Electrical results show a modest gain (10x) in the range where debye shielding of the electrolyte is similar to the nanopore dimensions. This opens the ability to electrically switch conducting biological fluids at the nanoscale, and we have built devices to this end. The ALD-based approach can fabricate trench-based horizontal nanochannels down to 8nm diameter. These devices are fabricated using ALD of both metals and oxides in a keyhole structure based on trenches patterned by e-beam lithography.