A method for forming a silicon carbide layer for use in integrated circuit fabrication is disclosed. The silicon carbide layer is formed by reacting a gas mixture comprising a silicon source, a carbon source, and an inert gas in the presence of an electric field. The electric field is generated using mixed frequency radio frequency (RF) power. The silicon carbide layer is compatible with integrated circuit fabrication processes. In one integrated circuit fabrication process, the silicon carbide layer is used as a hardmask for fabricating integrated circuit structures such as, for example, a damascene structure. In another integrated circuit fabrication process, the silicon carbide layer is used as an anti-reflective coating (ARC) for DUV lithography.