Abstract
Previous studies that have focused on the interactions of CH4/H2 and C2H2/H2 mixtures with the hot W filaments used for diamond chemical vapor deposition have been extended in order to determine the effect of oxygen on filament activity. The behavior of W filaments has now been studied up to 2300 °C in mixtures of 3% CH4/H2, with 0.5, 1.0, and 1.5% O2, at a pressure of 25 Torr. The effects of the addition of O2 on filament resistance, emissivity, and power consumption, as well as on the partial pressures of the gases (CH4, C2H2, O2, CO, and H2O ) in the reaction chamber, have been determined. The significant improvements in filament activity that are observed are shown to be due to removal of carbon from the filament surface by formation of CO. These results can be understood on the basis of our quasi-equilibrium thermodynamic model for the C–H–O system.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: Journal of Vacuum Science & Technology A: Vacuum, Surfaces, and Films
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
