Cardiff University | Prifysgol Caerdydd ORCA
Online Research @ Cardiff 
WelshClear Cookie - decide language by browser settings

Microwave plasma modelling in clamshell chemical vapour deposition diamond reactors

Cuenca, Jerome A. ORCID:, Mandal, Soumen ORCID:, Thomas, Evan L.H. and Williams, Oliver A. ORCID: 2022. Microwave plasma modelling in clamshell chemical vapour deposition diamond reactors. Diamond and Related Materials 124 , 108917. 10.1016/j.diamond.2022.108917

[thumbnail of 1-s2.0-S0925963522000991-main1.pdf] PDF - Published Version
Available under License Creative Commons Attribution.

Download (12MB)


A microwave plasma model of a chemical vapour deposition (CVD) reactor is presented for understanding spatial heteroepitaxial growth of polycrystalline diamond on Si. This work is based on the TM0(n>1) clamshell style reactor (Seki Diamond/ASTEX SDS 6K, Carat CTS6U, ARDIS-100 style) whereby a simplified H2 plasma model is used to show the radial variation in growth rate over small samples with different sample holders. The model uses several steps: an electromagnetic (EM) eigenfrequency solution, a frequency-transient EM/plasma fluid solution and a transient heat transfer solution at low and high microwave power densities. Experimental growths provide model validation with characterisation using Raman spectroscopy and scanning electron microscopy. This work demonstrates that shallow holders result in non-uniform diamond films, with a radial variation akin to the electron density, atomic H density and temperature distribution at the wafer surface. For the same process conditions, greater homogeneity is observed for taller holders, however, if the height is too extreme, the diamond quality reduces. From a modelling perspective, EM solutions are limited but useful for examining electric field focusing at the sample edges, resulting in accelerated diamond growth. For better accuracy, plasma fluid and heat transfer solutions are imperative for modelling spatial growth variation.

Item Type: Article
Date Type: Publication
Status: Published
Schools: Physics and Astronomy
Additional Information: This is an open access article under the CC BY license (
Publisher: Elsevier
ISSN: 0925-9635
Funders: EPSRC
Date of First Compliant Deposit: 21 March 2022
Date of Acceptance: 8 February 2022
Last Modified: 17 May 2023 20:54

Citation Data

Cited 2 times in Scopus. View in Scopus. Powered By Scopus® Data

Actions (repository staff only)

Edit Item Edit Item


Downloads per month over past year

View more statistics