High Growth Rate Diamond Synthesis in a Large Area Atmospheric Pressure Inductively Coupled Plasma
Abstract
Diamond synthesis is demonstrated in an atmospheric pressure inductively coupled argon-hydrogen-methane plasma. The plasma generated has a free stream active area of 20 sq cm and has an equilibrium electron temperature T sub e of approximately 4000 K. Growth rates are typically in the range of 25- 50 microns/hour and are found to depend on the processing conditions and position on the substrate. Individual crystallites are analyzed by micro-raman spectroscopy. Large (50 microns) size well-faceted crystallites are found to be under a state of compression, displaying shifts in the principal phonon mode as great as 3/cm from that of smaller polycrystalline diamond clusters or secondary nucleation sites. These shifts are shown to be expected within the framework of linear thermal expansion theory and the assumption of negligible stress relief at the crystallite-substrate interface. Keywords: Diamond synthesis, Thermal plasma, Raman spectroscopy.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 12, 1989
- Accession Number
- ADA216090
Entities
People
- C. H. Kruger
- M. A. Cappelli
- Mark S. Gordon
- T. Owano
Organizations
- Stanford University