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Title: Leaf-like nanotips synthesized on femtosecond laser-irradiated dielectric material

Abstract

Nanotips are the key nanostructures for the improvement of field emission, flat panel displays, force microscopy, and biosensor applications. We propose a single-step, rapid synthesis method to generate nanotips using femtosecond laser irradiation at megahertz frequency with a background flow of nitrogen gas at ambient conditions. Two different types of leaf-like nanotips can be grown on the target surface: randomly oriented multiple tips growing from a single large droplet and single tips growing from small droplets. In this report, we explain the mechanism accountable for the formation of such nanotips using known concepts of laser breakdown of dielectric materials, plasma plume generation, plasma interactions with incoming laser pulses and surrounding gas, as well as known thermal properties of target material. Nitrogen gas plays an interesting role for the resultant structural changes on the target surface and thus it is given special attention in our discussion. Our unique fabrication technique has enabled us to produce tips with nanoscale apexes with a stem and length ranging from few hundred nanometers to few micrometers.

Authors:
 [1]; ;  [2];  [3]
  1. Department of Mechanical Engineering, University of New Brunswick, Fredericton, New Brunswick, E3B 5A3 (Canada)
  2. Department of Aerospace Engineering, Ryerson University, Toronto, Ontario, M5B 2K3 (Canada)
  3. Department of Mechanical and Industrial Engineering, Ryerson University, Toronto, Ontario, M5B 2K3 (Canada)
Publication Date:
OSTI Identifier:
22413134
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 117; Journal Issue: 7; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; BREAKDOWN; DIELECTRIC MATERIALS; DROPLETS; FABRICATION; FIELD EMISSION; IRRADIATION; LASER RADIATION; MHZ RANGE; MICROSCOPY; NANOSTRUCTURES; NITROGEN; PLASMA; SURFACES; SYNTHESIS; THERMODYNAMIC PROPERTIES

Citation Formats

Kiani, Amirkianoosh, E-mail: a.kiani@unb.ca, Patel, Nikunj B., Tan, Bo, and Venkatakrishnan, Krishnan. Leaf-like nanotips synthesized on femtosecond laser-irradiated dielectric material. United States: N. p., 2015. Web. doi:10.1063/1.4913259.
Kiani, Amirkianoosh, E-mail: a.kiani@unb.ca, Patel, Nikunj B., Tan, Bo, & Venkatakrishnan, Krishnan. Leaf-like nanotips synthesized on femtosecond laser-irradiated dielectric material. United States. doi:10.1063/1.4913259.
Kiani, Amirkianoosh, E-mail: a.kiani@unb.ca, Patel, Nikunj B., Tan, Bo, and Venkatakrishnan, Krishnan. Sat . "Leaf-like nanotips synthesized on femtosecond laser-irradiated dielectric material". United States. doi:10.1063/1.4913259.
@article{osti_22413134,
title = {Leaf-like nanotips synthesized on femtosecond laser-irradiated dielectric material},
author = {Kiani, Amirkianoosh, E-mail: a.kiani@unb.ca and Patel, Nikunj B. and Tan, Bo and Venkatakrishnan, Krishnan},
abstractNote = {Nanotips are the key nanostructures for the improvement of field emission, flat panel displays, force microscopy, and biosensor applications. We propose a single-step, rapid synthesis method to generate nanotips using femtosecond laser irradiation at megahertz frequency with a background flow of nitrogen gas at ambient conditions. Two different types of leaf-like nanotips can be grown on the target surface: randomly oriented multiple tips growing from a single large droplet and single tips growing from small droplets. In this report, we explain the mechanism accountable for the formation of such nanotips using known concepts of laser breakdown of dielectric materials, plasma plume generation, plasma interactions with incoming laser pulses and surrounding gas, as well as known thermal properties of target material. Nitrogen gas plays an interesting role for the resultant structural changes on the target surface and thus it is given special attention in our discussion. Our unique fabrication technique has enabled us to produce tips with nanoscale apexes with a stem and length ranging from few hundred nanometers to few micrometers.},
doi = {10.1063/1.4913259},
journal = {Journal of Applied Physics},
number = 7,
volume = 117,
place = {United States},
year = {Sat Feb 21 00:00:00 EST 2015},
month = {Sat Feb 21 00:00:00 EST 2015}
}
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