1. A method of depositing a plurality of layers on an article comprising the steps of: flowing a plasma gas in at least one plasma generation chamber, the at least one plasma generation chamber being in communication with a deposition chamber, the deposition chamber having a lower pressure than the at least one plasma generation chamber, the article being disposed in the deposition chamber; generating at least one arc in the at least one plasma generation chamber to create at least one plasma which flows into the deposition chamber; injecting a first material into the at least one plasma to form a first layer on the article; and injecting a second material into the at least one plasma to form a second layer on the first layer, the second material comprising a gaseous reagent.