Low‐Temperature Synthesis of Diamond‐like Carbon Films on Steel Substrates by Electron‐Cyclotron‐Resonance Plasma‐Enhanced Chemical Vapor Deposition

Abstract

Using microwave electron‐cyclotron‐resonance plasma‐enhanced chemical vapor deposition, diamond‐like carbon films were directly grown at low temperatures (lessthan equal to400°C) on Fe‐based alloy substrates without diamond seeding or use of a template layer. A single, broad line in the Raman spectra was observed in the region of 1328‐1335 cm ‐1 for films grown in gas mixtures with a ratio of CH 4 :H 2 greaterthan equal to 2%. In contrast, disordered carbon and graphite phases appeared in the spectra for film grown with a concentration of 20% CH 4 in hydrogen. Diamond nucleation with an amorphous carbon layer was observed in the initial growth stage, while many diamond particles with irregular morphological features were observed on the surface of thicker films. These growth features are a consequence of the catalytic nature of the Fe‐based substrate.