Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
7898529 | Journal of the European Ceramic Society | 2018 | 25 Pages |
Abstract
Silicon carbide (SiC) layers were deposited onto alumina particles in a microwave plasma-assisted spouted bed reactor using methyltrichlorosilane (MTS) and hydrogen mixtures, in argon, as precursor gas feed. The operating parameters studied were enthalpy, gas composition, and pressure. Microwaves were guided from a generator, operating at 2.45 GHz, along a rectangular waveguide intersecting a quartz tube, acting as the reaction zone. A graphite nozzle at the bottom of the tube facilitated the spouting action. Growth rates varied from 50 to 140 μm/h. Overall results indicate that the optimal region for SiC deposition requires relatively high enthalpy (â¼5 MJ/kg) and pressure (>â60 kPa) conditions, with hydrogen-to-MTS ratios â¼5:1. The quality (i.e. crystallinity, particle size, Si/C ratios) of the layers improve at these conditions, at the cost of decreased deposition rates. Characterisation was done by XRD, FTIR, XPS, SEM, TEM and EDX, which assisted in developing colour and morphological charts to indicate the changes as a function of changing operating parameters. A microwave plasma spouted bed reactor is demonstrated to be a viable alternative technique for SiC layer deposition onto microspheres.
Related Topics
Physical Sciences and Engineering
Materials Science
Ceramics and Composites
Authors
J.H. van Laar, H. Bissett, J.C. Barry, I.J. van der Walt, P.L. Crouse,