The demand for low-cost transparent gas and moisture barrier materials initiates many activities in the area of roll-to-roll (R2R), CVD, thin film technology. The present article is an overview on the elaboration of plasma-enhanced (PE)CVD technology for R2R manufacturing of amorphous silicon carbide (SiC) barrier coatings applied on polymers. A prototype R2R PECVD reactor is designed and built for uniform coatings deposition on large area web-substrates. A key feature is the incorporation of the Penning discharge plasma source (PDPS) to provide magnetically confined, high-density plasma (HDP) with no excessive heat. Coatings are grown on a variety of polymer substrates using trimethylsilane ((CH3)3SiH) as the main organic precursor for delivery of active SiC species in the gas phase during deposition. A variety of analytical techniques are utilized to correlate process operating factors and plasma chemistry with coating composition and properties, in particular with the barrier performance and durability of barrier coated films (BCFs). The developed R2R PECVD technology demonstrates significant achievements in barrier performance with water vapor transmission rate (WVTR) of less than 5 × 10−4 g m−2 day−1 and durability of BCFs for more than 500 h under damp-heat conditions of 85 °C and 85% relative humidity (RH). Manufactured BCFs can be competitively implemented for protection against detrimental gasses in various applications, such as drug and food packaging, and flexible electronic devices, such as thin film batteries and solar cells, liquid-crystal (LCD), and light-emitting diode (LED) displays.