Resistive materials comprising mixed nanoscopic particles and carbon nanotubes

• US 9,755,170 B2
• Filed: 04/11/2016
• Issued: 09/05/2017
• Est. Priority Date: 11/19/2008
• Status: Active Grant

• Current Assignee: ZEON Corporation
• Original Assignee: Nantero Incorporated
• Inventors: Ghenciu, Eliodor G., Rueckes, Thomas, Yao, Thierry, Kocab, J. Thomas
• Primary Examiner(s): TOBERGTE, NICHOLAS J
• Application Number:
  US15/095,296
• Publication Number:
  US 20160226008A1
• Time in Patent Office: 512 Days
• CPC Class Codes: B82Y 10/00 Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic
• CPC Class Codes: G11C 13/0069 Writing or programming circuits or methods
• CPC Class Codes: G11C 13/025 using fullerenes, e.g. C60, or nanotubes, e.g. carbon or silicon nanotubes
• CPC Class Codes: G11C 2013/009 Write using potential difference applied between cell electrodes
• CPC Class Codes: G11C 2213/79 Array wherein the access device being a transistor
• CPC Class Codes: H10B 63/30 comprising selection components having three or more electrodes, e.g. transistors
• CPC Class Codes: H10K 10/50 Bistable switching devices
• CPC Class Codes: H10K 19/202 Integrated devices comprising a common active layer
• CPC Class Codes: H10K 71/12 using liquid deposition, e.g. spin coating
• CPC Class Codes: H10K 85/20 Carbon compounds, e.g. carbon nanotubes or fullerenes
• CPC Class Codes: H10K 85/221 Carbon nanotubes
• CPC Class Codes: H10N 70/021 Formation of switching materials, e.g. deposition of layers
• CPC Class Codes: H10N 70/20 Multistable switching devices, e.g. memristors
• CPC Class Codes: H10N 70/231 based on solid-state phase change, e.g. between amorphous and crystalline phases, Ovshinsky effect
• CPC Class Codes: H10N 70/826 adapted for essentially vertical current flow, e.g. sandwich or pillar type devices
• CPC Class Codes: H10N 70/8845 Carbon or carbides
• CPC Class Codes: Y10T 428/25 Web or sheet containing structurally defined element or component and including a second component containing structurally defined particles

Abstract

An improved switching material for forming a composite article over a substrate is disclosed. A first volume of nanotubes is combined with a second volume of nanoscopic particles in a predefined ration relative to the first volume of nanotubes to form a mixture. This mixture can then be deposited over a substrate as a relatively thick composite article via a spin coating process. The composite article may possess improved switching properties over that of a nanotube-only switching article. A method for forming substantially uniform nanoscopic particles of carbon, which contains one or more allotropes of carbon, is also disclosed.

Claims

1. A resistive material comprising:

a first volume of nanotubes; and

a second volume of nanoscopic particles in a predefined ratio relative to said first volume of nanotubes;

wherein said nanoscopic particles are silicon based particles.

2. The resistive material of claim 1 wherein said resistive material is a nanofabric.

3. The resistive material of claim 1 wherein said resistive material is a film.

4. The resistive material of claim 1 wherein said nanotubes comprising said first volume are substantially all carbon nanotubes.

5. The resistive material of claim 1 wherein said nanoscopic particles comprise carbon particles of substantially uniform diameter.

6. The resistive material of claim 1 wherein said second volume of nanoscopic particles includes nanoscopic particles containing at least one allotrope of carbon.

7. The resistive material of claim 1 wherein said second volume of nanoscopic particles includes multi-walled nanotubes.

8. The resistive material of claim 1 wherein substantially all of said nanoscopic particles within said second volume fall within a predetermined volume tolerance.

9. The resistive material of claim 1 wherein at least one of the magnitude of said first volume of nanotubes and the magnitude of said second volume of nanoscopic particles is selected to realize a desired volume density of nanotubes within said resistive material.

10. The resistive material of claim 1 wherein said first volume of nanotubes form a matrix phase and said second volume of nanoscopic particles form a discrete phase.

11. The resistive material of claim 1 wherein said second volume of nanoscopic particles form a matrix phase and said first volume of nanotubes form a discrete phase.

12. The resistive material of claim 1 wherein said first volume of nanotubes and said second volume of nanoscopic particles form interconnected matrix phases.

13. The resistive material of claim 1 wherein said resistive material has less than about 10¹¹ metal atoms/cm².

14. The resistive material of claim 1 wherein said resistive material is a homogeneous mixture of said first volume of nanotubes and said second volume of nanoscopic particles.

15. The resistive material of claim 1 wherein said resistive material is a heterogeneous mixture of said first volume of nanotubes and said second volume of nanoscopic particles.