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Title: Raman spectroscopy study of the influence of processing conditions on the structure of polycrystalline diamond films

Abstract

Diamond films are prepared by microwave plasma-enhanced chemical-vapor deposition on Si (100) substrates using the H{sub 2}-Ar-CH{sub 4} gases. Raman scattering data, including the peak position, intensity, area, and width, are analyzed in depth and used to obtain the sp{sup 3}- and sp{sup 2}-bonded carbon contents and the nature of internal stresses in the films. Polarization behavior of the Raman peaks is analyzed to assess its role on the quantitative analysis of the diamond films, which suggested that the 1150 cm{sup -1} Raman peak in nanocrystalline diamond films could be attributed to sp{sup 2}-bonded carbon. The role of the H{sub 2}/Ar content in the gas mixture and substrate temperature on the characteristics of the diamond film is studied. Thickness and grain size of diamond films are also determined by scanning electron microscopy and related to the deposition conditions and Raman results. Deposition conditions, which led to highest sp{sup 3}-bonded carbon content and growth rate, are identified.

Authors:
; ; ; ;  [1];  [2]
  1. Department of Chemical and Materials Engineering, University of Cincinnati, Cincinnati, Ohio 45221-0012 (United States)
  2. (United States)
Publication Date:
OSTI Identifier:
20777037
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Vacuum Science and Technology. A, International Journal Devoted to Vacuum, Surfaces, and Films; Journal Volume: 24; Journal Issue: 2; Other Information: DOI: 10.1116/1.2150228; (c) 2006 American Vacuum Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; CHEMICAL VAPOR DEPOSITION; DIAMONDS; GASES; GRAIN SIZE; HYDROGEN; METHANE; MICROWAVE RADIATION; MIXTURES; NANOSTRUCTURES; PEAKS; PLASMA; POLARIZATION; POLYCRYSTALS; RAMAN SPECTRA; RAMAN SPECTROSCOPY; SCANNING ELECTRON MICROSCOPY; STRESSES; SUBSTRATES; THIN FILMS

Citation Formats

Ramamurti, R., Shanov, V., Singh, R.N., Mamedov, S., Boolchand, P., and Department of Electrical and Computer Engineering and Computer Science, University of Cincinnati, Cincinnati, Ohio 45221-0030. Raman spectroscopy study of the influence of processing conditions on the structure of polycrystalline diamond films. United States: N. p., 2006. Web. doi:10.1116/1.2150228.
Ramamurti, R., Shanov, V., Singh, R.N., Mamedov, S., Boolchand, P., & Department of Electrical and Computer Engineering and Computer Science, University of Cincinnati, Cincinnati, Ohio 45221-0030. Raman spectroscopy study of the influence of processing conditions on the structure of polycrystalline diamond films. United States. doi:10.1116/1.2150228.
Ramamurti, R., Shanov, V., Singh, R.N., Mamedov, S., Boolchand, P., and Department of Electrical and Computer Engineering and Computer Science, University of Cincinnati, Cincinnati, Ohio 45221-0030. Wed . "Raman spectroscopy study of the influence of processing conditions on the structure of polycrystalline diamond films". United States. doi:10.1116/1.2150228.
@article{osti_20777037,
title = {Raman spectroscopy study of the influence of processing conditions on the structure of polycrystalline diamond films},
author = {Ramamurti, R. and Shanov, V. and Singh, R.N. and Mamedov, S. and Boolchand, P. and Department of Electrical and Computer Engineering and Computer Science, University of Cincinnati, Cincinnati, Ohio 45221-0030},
abstractNote = {Diamond films are prepared by microwave plasma-enhanced chemical-vapor deposition on Si (100) substrates using the H{sub 2}-Ar-CH{sub 4} gases. Raman scattering data, including the peak position, intensity, area, and width, are analyzed in depth and used to obtain the sp{sup 3}- and sp{sup 2}-bonded carbon contents and the nature of internal stresses in the films. Polarization behavior of the Raman peaks is analyzed to assess its role on the quantitative analysis of the diamond films, which suggested that the 1150 cm{sup -1} Raman peak in nanocrystalline diamond films could be attributed to sp{sup 2}-bonded carbon. The role of the H{sub 2}/Ar content in the gas mixture and substrate temperature on the characteristics of the diamond film is studied. Thickness and grain size of diamond films are also determined by scanning electron microscopy and related to the deposition conditions and Raman results. Deposition conditions, which led to highest sp{sup 3}-bonded carbon content and growth rate, are identified.},
doi = {10.1116/1.2150228},
journal = {Journal of Vacuum Science and Technology. A, International Journal Devoted to Vacuum, Surfaces, and Films},
number = 2,
volume = 24,
place = {United States},
year = {Wed Mar 15 00:00:00 EST 2006},
month = {Wed Mar 15 00:00:00 EST 2006}
}
  • Flat, low-stress, boron-doped polysilicon thin films were prepared on single crystalline silicon substrates by low pressure chemical vapor deposition. It was found that the polysilicon films with different deposition processing have different microstructure properties. The confinement effect, tensile stresses, defects, and the Fano effect all have a great influence on the line shape of Raman scattering peak. But the effect results are different. The microstructure and the surface layer are two important mechanisms dominating the internal stress in three types of polysilicon thin films. For low-stress polysilicon thin film, the tensile stresses are mainly due to the change of microstructuremore » after thermal annealing. But the tensile stresses in flat polysilicon thin film are induced by the silicon carbide layer at surface. After the thin film doped with boron atoms, the phenomenon of the tensile stresses increasing can be explained by the change of microstructure and the increase in the content of silicon carbide. We also investigated the disorder degree states for three polysilicon thin films by analyzing a constant C. It was found that the disorder degree of low-stress polysilicon thin film larger than that of flat and boron-doped polysilicon thin films due to the phase transformation after annealing. After the flat polysilicon thin film doped with boron atoms, there is no obvious change in the disorder degree and the disorder degree in some regions even decreases.« less
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