Fabrication of Conjugated Conducting Polymers by Chemical Vapor Deposition (CVD) Method.

Chemical vapor deposition (CVD) is a highly adaptable manufacturing technique used to fabricate high-quality thin films, making it essential across numerous industries. As materials fabrication processes progress, CVD has advanced to enable the precise deposition of both inorganic 2D materials, such as graphene and transition metal dichalcogenides, and high-quality polymeric thin films, offering excellent conformality and precise nanostructure control on a wide range of substrates. Conjugated conducting polymers have emerged as promising materials for next-generation electronic, optoelectronic, and energy storage devices due to their unique combination of electrical conductivity, optical transparency, ionic transport, and mechanical flexibility. Oxidative CVD (oCVD) involves the spontaneous reaction of oxidant and monomer vapors upon their adsorption onto the substrate surface, resulting in step-growth polymerization that commonly produces conducting or semiconducting polymer thin films. oCVD has gained significant attention for its ability to fabricate conjugated conducting polymers under vacuum conditions, allowing precise control over film thickness, doping levels, and nanostructure engineering. The low to moderate deposition temperature in the oCVD method enables the direct integration of conducting and semiconducting polymer thin films onto thermally sensitive substrates, including plants, paper, textiles, membranes, carbon fibers, and graphene. This review explores the fundamentals of the CVD process and vacuum-based manufacturing, while also highlighting recent advancements in the oCVD method for the fabrication of conjugated conducting and semiconducting polymer thin films.