A process for applying a silicon oxide barrier coating to a PET container, wherein the PET container comprises a wall having an inner surface and an outer surface, the process comprising the steps of: (a) heating a PET container such that at least the outer surface is at a temperature of from about 200° F. to about 383° F.; (b) forming a coated PET container by applying at least one silicon oxide barrier layer on at least the inner surface of the PET container while the temperature of at least the outer surface of the PET container is at a temperature of from about 200° F. to about 383° F.; and (c) cooling the coated PET container after step b.