摘要 |
A method for cleaning metallic impurities from a silicon surface of a semiconductor device is described. The first method includes, in sequence, the steps of: (a) exposing the silicon surface for a first time to a plasma afterglow anhydrous cleaning gas mixture containing nitric oxide and hydrogen chloride together with an inert carrier gas to remove metallic impurities, and then either; (b) exposing that surface for a second time to a plasma afterglow gas mixture of a fluorocarbon gas and hydrogen or carbon dioxide to remove the silicon oxynitrochloride film which is formed by step (a), leaving a fluorocarbon polymer film; and (c) exposing the surface for a third time to a plasma afterglow gas of oxygen to remove the fluorocarbon polymer film deposited in step (b); or (d) exposing that surface for a second time to a plasma afterglow gas mixture of inorganic fluorine compound gas, O2 and carrier gas to remove the silicon oxynitrochlorine film which is formed in step (a).
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