A process for coating of at least one conformal thin film simultaneously onto the surface of a plurality or batch of substrates having nanoscaled features is provided. The process involves exposing a batch of substrates to a supercritical fluid mixture in a controlled environment, and subsequently heating and cooling the substrate, in the presence of the supercritical fluid mixture, beyond a threshold temperature at which film growth can be enabled to initiate conformal thin film deposition on the surface of the substrate and within the nanoscaled features. The supercritical fluid mixture may be generated in a manner so as to maintain a necessary concentration level of the precursor material to permit sufficient thin film growth within the controlled environment. The supercritical fluid mixture may also be introduced into the controlled environment in a manner which minimizes precipitation or loss of solubility of the precursor material in the mixture. A system of thin film deposition of a batch of substrates is also provided.