Feedback control of dimensions in nanopore and nanofluidic devices
AssigneeInternational Business Machines Corporation
InventorsStefan Harrer, Stephen M. Rossnagel, Philip S. Waggoner
Life of this patent
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Abstract
Nanofluidic passages such as nanochannels and nanopores are closed or opened in a controlled manner through the use of a feedback system. An oxide layer is grown or removed within a passage in the presence of an electrolyte until the passage reaches selected dimensions or is closed. The change in dimensions of the nanofluidic passage is measured during fabrication. The ionic current level through the passage can be used to determine passage dimensions. Fluid flow through an array of fluidic elements can be controlled by selective oxidation of fluidic passages between elements.
Claims5
A method of fabricating a nanofluidic device, comprising:
- forming a nanofluidic passage having larger than targeted dimensions in a substrate, wherein the nanofluidic passage is a channel formed with an opening in a surface of the substrate;
- forming a conductive layer on the substrate, thereby reducing the dimensions of the nanofluidic passage and closing the opening;
- filling the nanofluidic passage with an electrolyte;
- electrochemically oxidizing the conductive layer until the fluidic passage has the targeted dimensions;
- monitoring the size of the nanofluidic passage by measuring ionic current through the nanofluidic channel;
- and
- discontinuing electrochemically oxidizing the conductive layer when the ionic current reaches a level corresponding to the targeted dimensions.
A method of fabricating a nanofluidic device, comprising:
- obtaining a structure including a base and a non-metallic layer on the base;
- forming a nanochannel within the non-metallic layer of the structure;
- forming an electrically conductive layer within the nanochannel, the electrically conductive layer forming a surface of the nanochannel having a bottom portion extending over the base and sidewall portions adjoining the non-metallic layer;
- electrochemically oxidizing the electrically conductive layer to reduce the dimensions of the nanochannel by:
- filling the nanochannel with an electrolyte;
- and
- applying a voltage to the electrically conductive layer, thereby forming an oxide layer on the electrically conductive layer, the oxide layer adjoining the bottom portion and the sidewall portions of the electrically conductive layer;
- creating an ionic current through the nanochannel;
- measuring the ionic current;
- monitoring the size of the nanofluidic passage by measuring ionic current through the nanochannel;
- and
- discontinuing electrochemically oxidizing the electrically conductive layer when the ionic current reaches a level corresponding to targeted dimensions of the nanochannel.
Dependencies are inferred from the claim text.