Microstructural Control of Pyrolytic Carbon Layer Deposited from Methane by Isotropic Chemical Vapor Infiltration

Pyrolytic carbon (PyC) layers were deposited using methane. The PyC layer deposited with 5% methane showed highly textured graphite, while that deposited using 100% methane showed low textured graphite. The degrees of anisotropy of the carbon layers were measured using an X-ray diffractometer, a transmission electron microscope, and a Raman spectroscope, and the results were compared with those reported previously. The orientation angles obtained from the fast Fourier transformation of the high-resolution transmission electron microscopy images and the ID/IG intensity ratios obtained from the Raman spectra were used to evaluate the anisotropy of the PyC layers.