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Title: Optical emission diagnostics of plasmas in chemical vapor deposition of single-crystal diamond

Here, a key aspect of single crystal diamond growth via microwave plasma chemical vapor deposition is in-process control of the local plasma-substrate environment, that is, plasma gas phase concentrations of activated species at the plasma boundary layer near the substrate surface. Emission spectra of the plasma relative to the diamond substrate inside the microwave plasma reactor chamber have been analyzed via optical emission spectroscopy. The spectra of radical species such as CH, C 2, and H (Balmer series) important for diamond growth were found to be more depndent on operating pressure than on microwave power. Plasma gas temperatures were calculated from measurements of the C 2 Swan band (d 3Π → a 3Π transition) system. The plasma gas temperature ranges from 2800 to 3400 K depending on the spatial location of the plasma ball, microwave power and operating pressure. Addition of Ar into CH 4 + H 2 plasma input gas mixture has little influence on the Hα, Hβ, and Hγ intensities and single-crystal diamond growth rates.
 [1] ;  [1]
  1. Carnegie Institution of Washington, Washington, D.C. (United States)
Publication Date:
Grant/Contract Number:
Accepted Manuscript
Journal Name:
Journal of Vacuum Science and Technology. A, Vacuum, Surfaces and Films
Additional Journal Information:
Journal Volume: 33; Journal Issue: 6; Journal ID: ISSN 0734-2101
American Vacuum Society
Research Org:
Carnegie Institution of Washington, Washington, D.C. (United States)
Sponsoring Org:
USDOE National Nuclear Security Administration (NNSA)
Country of Publication:
United States
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; microwave plasma; optical emission diagnostics; single-crystal diamond
OSTI Identifier: