A gas delivery system for a plasma process system such as a plasma etching system wherein inner surfaces of gas passages are coated with a corrosion-resistant material coating formed by curing a layer of fluidic precursor deposited on the inner surfaces. The coating can be formed by (a) flowing a fluidic precursor of a corrosion-resistant material through the gas passages and depositing a layer of the fluidic precursor to completely coat the inner surfaces of the gas passages; (b) removing excess fluidic precursor from the inner surfaces; (c) curing the deposited layer of the fluidic precursor to form a corrosion-resistant material coating.