Projects per year
Abstract
A microwave (MW) activated hydrogen plasma operating under conditions
relevant to contemporary diamond chemical vapor deposition reactors has
been investigated using a combination of experiment and self-consistent
2-D modeling. The experimental study returns spatially and wavelength
resolved optical emission spectra of the d → a (Fulcher), G → B, and e →
a emissions of molecular hydrogen and of the Balmer-α emission of
atomic hydrogen as functions of pressure, applied MW power, and
substrate diameter. The modeling contains specific blocks devoted to
calculating (i) the MW electromagnetic fields (using Maxwell’s
equations) self-consistently with (ii) the plasma chemistry and electron
kinetics, (iii) heat and species transfer, and (iv) gas–surface
interactions. Comparing the experimental and model outputs allows
characterization of the dominant plasma (and plasma emission) generation
mechanisms, identifies important coupling reactions between hydrogen
atoms and molecules (e.g., the quenching of H(n > 2) atoms and electronically excited H2 molecules (H2*) by the alternate ground-state species and H3+ ion formation by the associative ionization reaction of H(n = 2) atoms with H2), and illustrates how spatially resolved H2* (and Hα)
emission measurements offer a detailed and sensitive probe of the
hyperthermal component of the electron energy distribution function.
Original language | English |
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Pages (from-to) | 8286-8300 |
Number of pages | 15 |
Journal | Journal of Physical Chemistry A |
Volume | 122 |
Early online date | 25 Sept 2018 |
DOIs | |
Publication status | Published - 25 Oct 2018 |
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Dive into the research topics of 'Spatially Resolved Optical Emission and Modelling Studies of Microwave-Activated H2 Plasmas Operating under Conditions Relevant for Diamond Chemical Vapor Deposition'. Together they form a unique fingerprint.Projects
- 1 Finished
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Metrology concepts for a new generation of plasma manufacturing with atom-scale precision
Ashfold, M. N. R. (Principal Investigator)
1/07/13 → 21/12/18
Project: Research
Student theses
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Alternative Excitation Mechanisms Occurring within Microwave-activated Plasmas under Conditions Relevant to the Chemical Vapour Deposition of Diamond
Mahoney, E. J. D. (Author), Ashfold, M. (Supervisor) & Western, C. (Supervisor), 1 Oct 2019Student thesis: Doctoral Thesis › Doctor of Philosophy (PhD)
File
Datasets
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Data from plasma diagnosis (09-2018)
Ashfold, M. (Creator) & Mahoney, E. (Creator), University of Bristol, 18 Sept 2018
DOI: 10.5523/bris.2spimvgp4waj629g6zt6v6qil9, http://data.bris.ac.uk/data/dataset/2spimvgp4waj629g6zt6v6qil9
Dataset