lightweight, wearable, and stretchable properties of CPs relative to traditional materials highlight the areas where CPs may find their niche in modern devices. [2] The fabrication of uniform CPs in large scale with high throughput roll-to-roll process is of great importance in industrial sectors. To achieve this purpose, chemical vapor deposition (CVD) along with other vapor deposition methods are the promising approaches to expedite the commercialization process of CPs in large-scale applications.For polymers which dissolve, films can be formed by solution-based methods such as dip-coating and spin-coating. However, CPs, particularly those formed from unfunctionalized monomers, are often insoluble or require solvents which are unsafe and costly to use. The lack of solubility is typically associated with a rigid backbone structure that promotes crystallite formation. As a result, dissolution requires overcoming the associated enthalpy of crystallization.The need for solubilizing polymers is eliminated by employing CVD as the thin film formation technique. A variety of different CVD processes have been developed for vapor phase reactants to undergo similar polymerization mechanisms as those reported for solution synthesis. [3] These include CVD polymer methods for chain growth by free radical or cationic initiation, or by condensation polymerization. For most conjugated macromolecules, the desired variant of the CVD method needs to mimic the step-growth polymerization mechanism in order to obtain optimized properties, such as electrical conductivity. This motivated the invention of oxidative CVD (oCVD) in which the vacuum chamber design, strategy for reactant vapor introduction, and process conditions are optimized for step-growth polymerization. Vapor deposition methods which are not mechanistically motivated, such as thermal evaporation, pulsed laser deposition, and plasma-enhanced CVD, can result in conjugated polymer films having properties that are insufficient for integration into many types of devices. Thus, one major significance of achieving conjugated polymers having highly desirable characteristics by oCVD is the ability to fabricate state-of-the-art optoelectronic and energy storage devices.The oCVD process is a single-step method to convert vapor phase monomers, along with vapors of oxidant, into thin CP films. [3,4] At the surface of the substrate, step-growth Conducting polymers (CPs) combine electronic conductivity, optical transparency, and mechanical flexibility compatible with lightweight substrates. Due to these features CPs exhibit promising performance for a wide range of applications including electronic, optoelectronic, electrochemical, optochemical, and energy storage and harvesting devices. Fabrication of high-quality CPs thin film in a large scale is of high demand in multiple industrial sectors. Chemical vapor deposition (CVD) is a promising approach for scale-up and commercialization of CPs in large-scale thin film applications by a roll-to-roll process. The CVD technique is a versati...