Nanopillar field-effect and junction transistors with functionalized gate and base electrodes

• US 9,070,733 B2
• Filed: 07/12/2013
• Issued: 06/30/2015
• Est. Priority Date: 07/25/2012
• Status: Active Grant

• Current Assignee: California Institute of Technology, Sanofi
• Original Assignee: California Institute of Technology
• Inventors: Rajagopal, Aditya, Plettenburg, Oliver, Petry, Stefan, Scherer, Axel, Chang, Chieh-feng, Tschirhart, Charles L.
• Primary Examiner(s): Brown, Melanie Y
• Assistant Examiner(s): Crawford, Erik B
• Application Number:
  US13/941,295
• Publication Number:
  US 20140030819A1
• Time in Patent Office: 718 Days
• Field of Search: 422/82.01, 435/287.2, 435/7.1, 977/742, 977/762, 977/938, 977/700, 977/773, 977/904
• US Class Current: 1/1
• CPC Class Codes: B82Y 15/00 Nanotechnology for interacting, sensing or actuating, e.g. quantum dots as markers in protein assays or molecular motors
• CPC Class Codes: G01N 27/4145 specially adapted for biomolecules, e.g. gate electrode with immobilised receptors
• CPC Class Codes: G01N 27/4146 involving nanosized elements, e.g. nanotubes, nanowires
• CPC Class Codes: H01L 29/0676 oriented perpendicular or at an angle to a substrate
• CPC Class Codes: H01L 29/413 Nanosized electrodes, e.g. nanowire electrodes comprising one or a plurality of nanowires nanosized carbon materials, e.g. carbon nanotubes, per se C01B32/15; transparent electrodes comprising carbon nano-tubes H10K30/821, nanotechnology per se B82B
• CPC Class Codes: H01L 29/45 Ohmic electrodes
• CPC Class Codes: H01L 29/49 Metal-insulator-semiconductor electrodes, e.g. gates of MOSFET H01L29/435 takes precedence
• CPC Class Codes: H01L 29/73 Bipolar junction transistors
• CPC Class Codes: H01L 29/732 Vertical transistors
• CPC Class Codes: H01L 29/735 Lateral transistors
• CPC Class Codes: H01L 29/78 with field effect produced by an insulated gate H01L29/7725, H01L29/775, H01L29/778 take precedence

Abstract

Systems and methods for molecular sensing are described. Molecular sensors are described which are based on field-effect or bipolar junction transistors. These transistors have a nanopillar with a functionalized layer contacted to either the base or the gate electrode. The functional layer can bind molecules, which causes an electrical signal in the sensor.

Claims

1. A structure for sensing molecules, the structure comprising:

a semiconductor substrate;

a source region in the semiconductor substrate, the source region comprising a first doped semiconductor region;

a drain region in the semiconductor substrate, the drain region comprising a second doped semiconductor region;

a source electrode, contacted to the source region;

a drain electrode, contacted to the drain region;

a first insulating layer, covering at least in part one or more of the source electrode, the drain electrode, the source region, the drain region, and the semiconductor substrate;

a nanopillar, covered by a second insulating layer on bottom and lateral areas of the nanopillar and formed between the source region and the drain region; and

a functionalized gate electrode on a top area of the nanopillar.

2. The structure of claim 1, wherein the shape of the nanopillar is a cylindrical shape.

3. The structure of claim 1, wherein the functionalized gate electrode comprises two layers, or a matrix layer containing nanoparticles.

4. The structure of claim 1, wherein the functionalized gate electrode is made from a material selected from a group consisting of silicon, silicon oxide, sapphire, aluminum, copper, rhodium, gallium, palladium, platinum, iridium, Ag—

AgCl, gold, and Pt—

PtRu.

5. The structure of claim 1, wherein the nanopillar is configured to directly facilitate electrochemical reactions on its surface.

6. The structure of claim 1, wherein the functionalized gate electrode comprises antibodies for antigen capture.

7. The structure of claim 1, wherein the functionalized gate electrode can bind to molecules, wherein the molecules comprise chemical and biological molecules.

8. The structure of claim 7, wherein the biological molecules comprise DNA.

9. A method for detecting molecules with the structure of claim 1, the method comprising:

providing a gas and/or fluid solution;

contacting the solution to the functionalized gate electrode;

detecting the molecules based on an electrical signal between the source region and the drain region.

10. The structure of claim 1, wherein the shape of the nanopillar is a rectangular shape.

11. The structure of claim 1, wherein the shape of the nanopillar is a tapered shape.