The method according to claim 1, wherein the third step comprises a period of supplying the second process gas to the process field while exciting the second process gas by an exciting mechanism.

• 如请求项1之方法，其中该第三步骤包含将该第二制程气体供应至该制程区域同时藉由一激发机制来激发该第二制程气体的一周期。