Sensor having a thin-film inhibition layer

• US 8,754,454 B2
• Filed: 04/11/2011
• Issued: 06/17/2014
• Est. Priority Date: 05/19/2005
• Status: Active Grant

• Current Assignee: Nanomix Incorporated (CJY Holdings Ltd.)
• Original Assignee: Nanomix Incorporated (CJY Holdings Ltd.)
• Inventors: Bryant, Craig, Chang, Ying-Lan, Gabriel, Jean-Christophe P., Johnson, Bradley N., Kuzmych, Oleksandr, Mickelson, William, Passmore, John Loren, Skarupo, Sergei, Valcke, Christian
• Primary Examiner(s): YUSHIN, NIKOLAY K
• Application Number:
  US13/084,465
• Publication Number:
  US 20120006102A1
• Time in Patent Office: 1,163 Days
• Field of Search: 257/252, 257/253, 257/414, 977/712, 977/932, 977/953, 977/957
• US Class Current: 257/253
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: G01N 27/127 comprising nanoparticles
• CPC Class Codes: G01N 27/4146 involving nanosized elements, e.g. nanotubes, nanowires
• CPC Class Codes: G01N 33/0037 for NOx
• CPC Class Codes: G01N 33/004 for CO, CO2
• CPC Class Codes: G01N 33/497 of gaseous biological material, e.g. breath
• CPC Class Codes: Y02A 50/20 Air quality improvement or preservation, e.g. vehicle emission control or emission reduction by using catalytic converters

Abstract

Sensors and detection systems suitable for measuring analytes, such as biomolecule, organic and inorganic species, including environmentally and medically relevant volatiles and gases, such as NO, NO2, CO2, NH3, H2, CO and the like, are provided. Certain embodiments of nanostructured sensor systems are configured for measurement of medically important gases in breath. Applications include the measurement of endogenous nitric oxide (NO) in breath, such as for the monitoring or diagnosis of asthma and other pulmonary conditions.

Claims

1. A sensor device for detecting an analyte species in a fluid sample medium, comprising:

(a) a substrate having a substrate surface;

(b) one or more nanostructures disposed over the substrate surface;

(c) one or more conducting elements in electrical communication with the nanostructure and configured to communicate with measurement circuitry, wherein the conducting elements comprises conductive ink traces; and

(d) a layer coating at least a portion of the substrate surface, wherein the substrate and the nanostructures are differentially coated with said layer such that at least a portion of the nanostructures are exposed to permit interaction with the sample medium, wherein the layer inhibits at least one interaction between the substrate surface and the sample medium, so as to prevent or reduce at least one interference response of the device which would be detectable by the measurement circuitry via the one or more conducting elements in the absence of the layer, and wherein the coated portions of the substrate surface contact the layer.

2. The sensor device of claim 1 wherein at least a portion of one or more conducting elements are coated with said layer and said layer inhibits at least one interaction between the one or more conducting elements and the sample medium, so as to prevent or reduce at least one interference response which would be detectable by the measurement circuitry in the absence of the layer.

3. The sensor device of claim 1 wherein the layer is deposited by an atomic layer deposition method.

4. The sensor device of claim 1, wherein the layer has a thickness between about 1 nm and 10 nm.

5. The sensor device of claim 1, wherein the layer has a thickness of less than 5 nm.

6. The sensor device of claim 1, wherein the layer comprises one or both of Al2O3 or ZrO2.

7. The sensor device of claim 1, wherein the device is configured to have a sensitivity to at least one of NO and NO2.

8. The sensor device of claim 1 wherein the layer inhibits oxidation of at least one of:

the substrate surface, the one or more conducting elements, and the one or more nanostructures.

9. The sensor device of claim 1 wherein the one or more nanostructures comprises a random network of carbon nanotubes.

10. The sensor device of claim 9 wherein the one or more conducting elements comprises at least one spaced-apart source-drain pair of contacts;

and wherein the random network is configured so that substantially no nanotube of the network is in contact with both the source and the drain contact.

11. The sensor device of claim 1 wherein substantially all of the substrate surface in between nanostructures is coated with said layer.

12. The sensor device of claim 1 further comprising a chemical species attached to or disposed on the differential coating, wherein said species is configured to interact with the analyte species.

13. The sensor device of claim 1 wherein the sensor device is an electrochemical sensing device.

14. The sensor device of claim 1 wherein the layer is a dielectric layer.

15. The sensor device of claim 1 wherein the sensor device is an electrochemical sensor.

16. The sensor device of claim 1 wherein one or more nanostructures are on an electrode on substrate surface.

17. The sensor device of claim 1 wherein the electrode is a carbon paste electrode.

18. The sensor device of claim 1 wherein the substrate is a flexible polymer sheet.