Well-faceted microcrystalline diamond (MCD) films were deposited along with nanocrystalline diamond (NCD) films on the same substrate by a microwave plasma in the gas mixture of 1% CH44 + 5% H2 + 94% Ar. This was achieved by forcing a microwave plasma ball generated at 170 torr gas pressure to touch a silicon substrate that was pre-seeded by nanocrystalline diamond powder resulting in a high concentration of atomic hydrogen on the surface of growing diamond. Previously reported compositional mapping of the argon-methane hydrogen system for MCD and NCD growth was not valid in this process parameter space. The non-uniform concentrations of atomic hydrogen and carbon containing radicals such as Ca as well as varied local substrate temperature resulted in the simultaneous deposition of well-faceted MCD films in some areas with nanograined NCD films in others. Dilution of methane/hydrogen microwave plasmas by as much as 94% of argon alone could not suppress the growth of MCD.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Mechanical Engineering
- Materials Chemistry
- Electrical and Electronic Engineering