Nanopore sensor device

• US 8,900,975 B2
• Filed: 01/03/2013
• Issued: 12/02/2014
• Est. Priority Date: 01/03/2013
• Status: Expired due to Fees

• Current Assignee: GlobalFoundries, Inc.
• Original Assignee: International Business Machines Corporation
• Inventors: Chang, Josephine B., Guillorn, Michael A., Joseph, Eric A., Papa Rao, Satyavolu S.
• Primary Examiner(s): Landau, Matthew
• Assistant Examiner(s): Anya, Igwe U
• Application Number:
  US13/733,404
• Publication Number:
  US 20140183667A1
• Time in Patent Office: 698 Days
• Field of Search: 438/478
• US Class Current: 438/478
• CPC Class Codes: B01L 3/502707 characterised by the manufacture of the container or its components by shaping or joining plastic parts B29C59/00, B29C65/00; by laminating B32B37/00; manufacture of microstructural devices in general B81C
• CPC Class Codes: G01N 33/48721 Investigating individual macromolecules, e.g. by translocation through nanopores Coulter counters in general G01N15/12; fabrication methods for nanoscale apertures B81B1/00; sequencing of nucleic acids C12Q1/68
• CPC Class Codes: G01N 33/54373 involving physiochemical end-point determination, e.g. wave-guides, FETS, gratings
• CPC Class Codes: H01L 29/66 Types of semiconductor device ; Multistep manufacturing processes therefor
• CPC Class Codes: H01L 29/66007 Multistep manufacturing processes

Abstract

A pair of electrode plates can be provided by directional deposition and patterning of a conductive material on sidewalls of a template structure on a first dielectric layer. An electrode line straddling the center portion is formed. A dielectric spacer and a conformal conductive layer are subsequently formed. Peripheral electrodes laterally spaced from the electrode line are formed by pattering the conformal conductive layer. After deposition of a second dielectric material layer that encapsulates the template structure, the template structure is removed to provide a cavity that passes through the pair of electrode plates, the electrode line, and the peripheral electrodes. A nanoscale sensor thus formed can electrically characterize a nanoscale string by passing the nanoscale string through the cavity while electrical measurements are performed employing the various electrodes.

Claims

1. A method of forming a sensor structure, said method comprising:

forming a template structure on a first dielectric material layer,

forming an electrode line straddling said template structure;

forming a dielectric spacer around said electrode line;

forming peripheral electrodes laterally spaced from said electrode line by said dielectric spacer;

forming a second dielectric material layer over said template structure; and

removing said template structure selective to said first and second dielectric material layers to form a cavity, wherein a sensor structure comprising said cavity and at least said electrode line is formed.

2. The method of claim 1, wherein said peripheral electrodes are formed by:

depositing a conformal conductive layer on said dielectric spacer; and

patterning said conformal conductive layer into said peripheral electrodes.

3. The method of claim 2, wherein said patterning of said conformal conductive layer comprises:

forming a photoresist layer over said conformal conductive layer;

patterning said photoresist layer such that a remaining portion of said photoresist layer straddles said electrode line; and

performing an anisotropic etch on said conformal conductive layer employing said patterned photoresist layer as an etch mask.

4. The method of claim 3, wherein remaining portions of said conformal conductive layer after said anisotropic etch include:

portions of said conformal conductive layer underneath said photoresist layer; and

vertical portions of said conformal conductive layer that are not covered by the lithographically patterned photoresist layer remain after said anisotropic etching.

5. The method of claim 3, further comprising removing a portion of said conformal conductive layer from above a top surface of said electrode line after said anisotropic etch, wherein two remaining disjoined portions of said conformal conductive layer constitute said peripheral electrodes.

6. The method of claim 5, wherein said second dielectric material layer are formed over said conformal conductive layer, and said method further comprises physically exposing a top surface of said portion of said conformal conductive layer by forming a cavity in said conformal conductive layer, wherein said portion of said conformal conductive layer is removed by an etch.

7. The method of claim 6, further comprising filling said cavity with a dielectric fill material, wherein said dielectric fill material is deposited directly on said electrode line.

8. The method of claim 3, wherein said remaining portion of said photoresist layer cover horizontal portions of said conformal conductive layer contacting said first dielectric material layer.

9. The method of claim 2, wherein said conformal conductive layer is deposited directly on a top surface of said electrode line.

10. The method of claim 2, wherein said conformal conductive layer is deposited directly on outer sidewall surfaces of said dielectric spacer.

11. The method of claim 2, wherein said conformal conductive layer is deposited directly on a top surface of said first dielectric material layer.

12. A method of forming a sensor structure, said method comprising:

forming a template structure on a first dielectric material layer, wherein template structure comprises;

a uniform width semiconductor region having a uniform width throughout;

a first tapered semiconductor region adjoined to said uniform width semiconductor region at a proximal end thereof and having a first variable width that increases with distance from said uniform width semiconductor region; and

a second tapered semiconductor region adjoined to said uniform width semiconductor region at a proximal end thereof and having a second variable width that increases with distance from said uniform width semiconductor region;

forming an electrode line straddling said template structure;

forming a second dielectric material layer over said template structure; and

removing said template structure selective to said first and second dielectric material layers to form a cavity, wherein a sensor structure comprising said cavity and at least said electrode line is formed.

13. A method of forming a sensor structure, said method comprising:

forming a template structure on a first dielectric material layer,

forming an electrode line straddling said template structure;

forming a dielectric spacer around said electrode line;

forming peripheral electrodes laterally spaced from said electrode line by said dielectric spacer;

forming a second dielectric material layer over said template structure;

forming at least one via cavity through said second dielectric material layer, wherein a surface of said template structure is physically exposed at a bottom of each of said at least one via cavity; and

removing said template structure selective to said first and second dielectric material layers to form a cavity that is contiguously connected to said at least one via cavity, wherein a sensor structure comprising said cavity and at least said electrode line is formed.

14. The method of claim 13, wherein said peripheral electrodes are formed by:

depositing a conformal conductive layer on said dielectric spacer; and

patterning said conformal conductive layer into said peripheral electrodes.

15. The method of claim 14, wherein said patterning of said conformal conductive layer comprises:

forming a photoresist layer over said conformal conductive layer;

patterning said photoresist layer such that a remaining portion of said photoresist layer straddles said electrode line; and

performing an anisotropic etch on said conformal conductive layer employing said patterned photoresist layer as an etch mask.

16. The method of claim 15, wherein remaining portions of said conformal conductive layer after said anisotropic etch include:

portions of said conformal conductive layer underneath said photoresist layer; and

vertical portions of said conformal conductive layer that are not covered by the lithographically patterned photoresist layer remain after said anisotropic etching.

17. The method of claim 15, further comprising removing a portion of said conformal conductive layer from above a top surface of said electrode line after said anisotropic etch, wherein two remaining disjoined portions of said conformal conductive layer constitute said peripheral electrodes.

18. The method of claim 14, wherein said conformal conductive layer is deposited directly on a top surface of said first dielectric material layer.

19. The method claim 13, wherein template structure comprises:

a uniform width semiconductor region having a uniform width throughout;

a first tapered semiconductor region adjoined to said uniform width semiconductor region at a proximal end thereof and having a first variable width that increases with distance from said uniform width semiconductor region; and

a second tapered semiconductor region adjoined to said uniform width semiconductor region at a proximal end thereof and having a second variable width that increases with distance from said uniform width semiconductor region.