Centimeter-scale high resolution metrology of entire CVD grown graphene sheets

Patent metadata

Field	Value
Publication number	US-9464990-B2
Application number	US-201314412948-A
Country	US
Kind code	B2
Filing date	Jul 3, 2013
Priority date	Jul 6, 2012
Publication date	Oct 11, 2016
Grant date	Oct 11, 2016

Abstract

A method for quick and easy identification of layer thickness and uniformity of entire large-area graphene samples on arbitrary substrates utilizing fluorescence quenching microscopy in which a polymer mixed with fluorescent dye is applied onto the graphene, then viewing the sample under a fluorescence microscope. A large-scale, high-resolution montage image of the sample is obtained for histogram-based segmentation based on contrast relative to the substrates.

First claim

The invention claimed is:

1. A method for analyzing graphene comprising
performing fluorescence quenching microscopy on a graphene sample to identify graphene layers on arbitrary substrates, the fluorescence quenching microscopy includes:
applying a polymer mixed with fluorescent dye onto the graphene then viewing the sample under a fluorescence microscope, wherein the polymer and dye mixture is applied by spin-coating a solution of the polymer and dye mixture onto the graphene sample, wherein the solution include toluene; and wherein the graphene layers are identified by performing a histogram-based segmentation based on contrast relative to the substrates.

2. The method of claim 1 in which the polymer is a cured poly(methyl methacrylate).

3. The method of claim 2 in which the polymer is removed by soaking in acetone and including the initial step, prior to said soaking with acetone, of applying a small amount of either acetone or poly(methyl methacrylate) to the polymer and drying said applied acetone or poly(methyl methacrylate).

4. The method of claim 3 in which individual images of the graphene sample are obtained to collect a montage of the images.

5. The method of claim 3 , in which the graphene layers are identified by performing a histogram-based segmentation based on contrast relative to the substrates.

6. The method of claim 5 , wherein the segmentation step comprises of collecting a large-scale, high-resolution montage image of the sample and processing the image to remove the effects of non-uniform illumination.

7. The method of claim 6 wherein the effects of non-uniform illumination is removed by applying the polymer and dye mixture onto a substrate bare of graphene and creating a correction image thereof using the same imaging pathway used to create the montage image.

8. The method of claim 1 in which individual images of the graphene sample are obtained to collect a montage of the images.

9. The method of claim 8 , in which the graphene layers are identified by performing a histogram-based segmentation based on contrast relative to the substrates.

10. The method of claim 9 , wherein the segmentation step comprises of collecting a large-scale, high-resolution montage image of the sample and processing the image to remove the effects of non-uniform illumination.

11. The method of claim 10 wherein the effects of non-uniform illumination is removed by applying the polymer and dye mixture onto a substrate bare of graphene and creating a correction image thereof using the same imaging pathway used to create the montage image.

12. The method of claim 1 , wherein the segmentation step comprises of collecting a large-scale, high-resolution montage image of the sample and processing the image to remove the effects of non-uniform illumination.

13. The method of claim 12 wherein the effects of non-uniform illumination is removed by applying the polymer and dye mixture onto a substrate bare of graphene and creating a correction image thereof using the same imaging pathway used to create the montage image.

14. A method for analyzing graphene comprising
performing fluorescence quenching microscopy on a graphene sample to identify graphene layers on arbitrary substrates, the fluorescence quenching microscopy including applying a polymer mixed with fluorescent dye onto the graphene then viewing the sample under a fluorescence microscope, wherein the polymer is removed by soaking in acetone and including the initial step, prior to said soaking with acetone, of applying a small amount of either acetone or poly(methyl methacrylate) to the polymer and drying said applied acetone or poly(methyl methacrylate).

15. A method for analyzing graphene comprising
performing fluorescence quenching microscopy on a graphene sample to identify graphene layers on arbitrary substrates, the fluorescence quenching microscopy including applying a polymer mixed with fluorescent dye onto the graphene then viewing the sample under a fluorescence microscope, and the graphene layers are identified by performing a histogram-based segmentation based on contrast relative to the substrates.

Assignees

• Univ California

Inventors

• Kyle Jennifer Reiber
• Ozkan Cengiz S
• Ozkan Mihrimah

Classifications

• G01N21/643

  non-biological material · CPC title

• G01N2223/406

  fluoroscopic image · CPC title

• G01N21/6458 Primary

  Fluorescence microscopy (fluorescence microscopes per se G02B21/0076 and G02B21/16) · CPC title

• G01N21/65

  Raman scattering · CPC title

• G01N2021/6417

  Spectrofluorimetric devices · CPC title