Image Analysis for SWNT Growth on Shutter Sputtered Catalyst

Abstract

Carbon Nanotubes (CNTs) have been used in remarkable ways since their discovery in 1991 by Sumio Iijima. Properties such as high thermal conductivity, good mechanical strength, and electrical conductivity are what make CNTs attractive. Some of their applications include water filtration, vehicles, energy storage, and now there is great potential in the biomedical field for CNTs as composites in tissue engineering, therapeutics carrier across the blood-brain barrier, cancer treatment, and much more. The issue that comes with Single-Walled Nanotubes (SWNTs) however is Ostwald ripening of catalyst and low CNT production. It is difficult to control gas parameters for hydrogen and argon and can be dangerous in a smaller lab, so acetylene without dilution gas is used. The method proposed here utilizes shutter sputtering of Iron on a th-SiO2/AlO substrate, followed by thermal chemical vapor deposition (CVD) for annealing. Shutter sputtering allows greater particle adhesion to the substrate due to wavelength and energy changes, allowing smaller catalysts to grow and a greater possibility of long SWNTs. We compare the effects of Ostwald ripening on catalysts formed onCarbon Nanotubes (CNTs) have been used in remarkable ways since their discovery in 1991 by Sumio Iijima. Properties such as high thermal conductivity, good mechanical strength, and electrical conductivity are what make CNTs attractive. Some of their applications include water filtration, vehicles, energy storage, and now there is great potential in the biomedical field for CNTs as composites in tissue engineering, therapeutics carrier across the blood-brain barrier, cancer treatment, and much more. The issue that comes with Single-Walled Nanotubes (SWNTs) however is Ostwald ripening of catalyst and low CNT production. It is difficult to control gas parameters for hydrogen and argon and can be dangerous in a smaller lab, so acetylene without dilution gas is used. The method proposed here utilizes shutter sputtering of Iron on a th-SiO2/AlO substrate, followed by thermal chemical vapor deposition (CVD) for annealing. Shutter sputtering allows greater particle adhesion to the substrate due to wavelength and energy changes, allowing smaller catalysts to grow and a greater possibility of long SWNTs. We compare the effects of Ostwald ripening on catalysts formed on a Fe shutter sputtered substrate annealed at 730°C and another at 760°C, in order to identify the correlation between the size and distance of catalyst particles for SWNT growths through Atomic Force Microscopy (AFM) image analysis. a Fe shutter sputtered substrate annealed at 730°C and another at 760°C, in order to identify the correlation between the size and distance of catalyst particles for SWNT growths through Atomic Force Microscopy (AFM) image analysis.