A method of depositing a protective coating containing silicon or metal material on a semiconductor substrate includes sputtering a material from the electrode on the semiconductor substrate in the plasma processing room. It can be deposited on the multi-storey mask coated with low-k material and/or low-k materials. The method can be used in the dual-embedded process, in order to protect the maskand enhance the etching selecting rate, choose to work in the etching process of stripping the protection of low-k materials by carbon depletion effects, and/or to prevent low-k materials absorb wet steam .