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Title: Ellipsometric investigation of nitrogen doped diamond thin films grown in microwave CH{sub 4}/H{sub 2}/N{sub 2} plasma enhanced chemical vapor deposition

Abstract

The influence of N{sub 2} concentration (1%–8%) in CH{sub 4}/H{sub 2}/N{sub 2} plasma on structure and optical properties of nitrogen doped diamond (NDD) films was investigated. Thickness, roughness, and optical properties of the NDD films in the VIS–NIR range were investigated on the silicon substrates using spectroscopic ellipsometry. The samples exhibited relatively high refractive index (2.6 ± 0.25 at 550 nm) and extinction coefficient (0.05 ± 0.02 at 550 nm) with a transmittance of 60%. The optical investigation was supported by the molecular and atomic data delivered by Raman studies, bright field transmission electron microscopy imaging, and X-ray photoelectron spectroscopy diagnostics. Those results revealed that while the films grown in CH{sub 4}/H{sub 2} plasma contained micron-sized diamond grains, the films grown using CH{sub 4}/H{sub 2}/(4%)N{sub 2} plasma exhibited ultranano-sized diamond grains along with n-diamond and i-carbon clusters, which were surrounded by amorphous carbon grain boundaries.

Authors:
 [1];  [2]; ;  [3];  [4]; ;  [5];  [1];  [6];  [7]
  1. Department of Metrology and Optoelectronics, Faculty of Electronics, Telecommunications and Informatics, Gdansk University of Technology, 11/12 G. Narutowicza St., 80-233 Gdansk (Poland)
  2. (IMO), Hasselt University, Wetenschapspark 1, B-3590 Diepenbeek (Belgium)
  3. Institute for Materials Research (IMO), Hasselt University, Wetenschapspark 1, B-3590 Diepenbeek (Belgium)
  4. (Belgium)
  5. Department of Electrochemistry, Corrosion and Material Engineering, Gdansk University of Technology, 11/12 Narutowicza St., 80-233 Gdansk (Poland)
  6. (United States)
  7. Department of Physics, Tamkang University, Tamsui 251, Taiwan (China)
Publication Date:
OSTI Identifier:
22590781
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 108; Journal Issue: 24; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; CHEMICAL VAPOR DEPOSITION; DIAMONDS; DOPED MATERIALS; ELLIPSOMETRY; GRAIN BOUNDARIES; METHANE; MICROWAVE RADIATION; NITROGEN; PLASMA; REFRACTIVE INDEX; ROUGHNESS; THICKNESS; THIN FILMS; TRANSMISSION ELECTRON MICROSCOPY; X-RAY PHOTOELECTRON SPECTROSCOPY

Citation Formats

Ficek, Mateusz, E-mail: rbogdan@eti.pg.gda.pl, Institute for Materials Research, Sankaran, Kamatchi J., Haenen, Ken, IMOMEC, IMEC vzw, Wetenschapspark 1, B-3590 Diepenbeek, Ryl, Jacek, Darowicki, Kazimierz, Bogdanowicz, Robert, Materials and Process Simulation Center, California Institute of Technology, Pasadena, California 91125, and Lin, I-Nan. Ellipsometric investigation of nitrogen doped diamond thin films grown in microwave CH{sub 4}/H{sub 2}/N{sub 2} plasma enhanced chemical vapor deposition. United States: N. p., 2016. Web. doi:10.1063/1.4953779.
Ficek, Mateusz, E-mail: rbogdan@eti.pg.gda.pl, Institute for Materials Research, Sankaran, Kamatchi J., Haenen, Ken, IMOMEC, IMEC vzw, Wetenschapspark 1, B-3590 Diepenbeek, Ryl, Jacek, Darowicki, Kazimierz, Bogdanowicz, Robert, Materials and Process Simulation Center, California Institute of Technology, Pasadena, California 91125, & Lin, I-Nan. Ellipsometric investigation of nitrogen doped diamond thin films grown in microwave CH{sub 4}/H{sub 2}/N{sub 2} plasma enhanced chemical vapor deposition. United States. doi:10.1063/1.4953779.
Ficek, Mateusz, E-mail: rbogdan@eti.pg.gda.pl, Institute for Materials Research, Sankaran, Kamatchi J., Haenen, Ken, IMOMEC, IMEC vzw, Wetenschapspark 1, B-3590 Diepenbeek, Ryl, Jacek, Darowicki, Kazimierz, Bogdanowicz, Robert, Materials and Process Simulation Center, California Institute of Technology, Pasadena, California 91125, and Lin, I-Nan. 2016. "Ellipsometric investigation of nitrogen doped diamond thin films grown in microwave CH{sub 4}/H{sub 2}/N{sub 2} plasma enhanced chemical vapor deposition". United States. doi:10.1063/1.4953779.
@article{osti_22590781,
title = {Ellipsometric investigation of nitrogen doped diamond thin films grown in microwave CH{sub 4}/H{sub 2}/N{sub 2} plasma enhanced chemical vapor deposition},
author = {Ficek, Mateusz, E-mail: rbogdan@eti.pg.gda.pl and Institute for Materials Research and Sankaran, Kamatchi J. and Haenen, Ken and IMOMEC, IMEC vzw, Wetenschapspark 1, B-3590 Diepenbeek and Ryl, Jacek and Darowicki, Kazimierz and Bogdanowicz, Robert and Materials and Process Simulation Center, California Institute of Technology, Pasadena, California 91125 and Lin, I-Nan},
abstractNote = {The influence of N{sub 2} concentration (1%–8%) in CH{sub 4}/H{sub 2}/N{sub 2} plasma on structure and optical properties of nitrogen doped diamond (NDD) films was investigated. Thickness, roughness, and optical properties of the NDD films in the VIS–NIR range were investigated on the silicon substrates using spectroscopic ellipsometry. The samples exhibited relatively high refractive index (2.6 ± 0.25 at 550 nm) and extinction coefficient (0.05 ± 0.02 at 550 nm) with a transmittance of 60%. The optical investigation was supported by the molecular and atomic data delivered by Raman studies, bright field transmission electron microscopy imaging, and X-ray photoelectron spectroscopy diagnostics. Those results revealed that while the films grown in CH{sub 4}/H{sub 2} plasma contained micron-sized diamond grains, the films grown using CH{sub 4}/H{sub 2}/(4%)N{sub 2} plasma exhibited ultranano-sized diamond grains along with n-diamond and i-carbon clusters, which were surrounded by amorphous carbon grain boundaries.},
doi = {10.1063/1.4953779},
journal = {Applied Physics Letters},
number = 24,
volume = 108,
place = {United States},
year = 2016,
month = 6
}
  • Diamond-like nanocomposite (DLN) thin films, comprising the networks of a-C:H and a-Si:O were deposited on pyrex glass or silicon substrate using gas precursors (e.g., hexamethyldisilane, hexamethyldisiloxane, hexamethyldisilazane, or their different combinations) mixed with argon gas, by plasma enhanced chemical vapor deposition technique. Surface morphology of DLN films was analyzed by atomic force microscopy. High-resolution transmission electron microscopic result shows that the films contain nanoparticles within the amorphous structure. Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, and x-ray photoelectron spectroscopy (XPS) were used to determine the structural change within the DLN films. The hardness and friction coefficient of the films weremore » measured by nanoindentation and scratch test techniques, respectively. FTIR and XPS studies show the presence of C-C, C-H, Si-C, and Si-H bonds in the a-C:H and a-Si:O networks. Using Raman spectroscopy, we also found that the hardness of the DLN films varies with the intensity ratio I{sub D}/I{sub G}. Finally, we observed that the DLN films has a better performance compared to DLC, when it comes to properties like high hardness, high modulus of elasticity, low surface roughness and low friction coefficient. These characteristics are the critical components in microelectromechanical systems (MEMS) and emerging nanoelectromechanical systems (NEMS).« less
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