| 摘要 |
PURPOSE: A method for simultaneously etching a nitride layer as well as an oxide layer by employing an etching apparatus for the oxide layer is provided. CONSTITUTION: A commonly used oxide etching apparatus uses a mixed etching gas of CHF3, CF4, and Ar with a ratio of 1:2.6:30. The apparatus is, however, not used for a nitride etching since an etching rate becomes lower to 2600 angstrom per minutes. Accordingly, in the light of a fact that the etching rate of the nitride layer mostly relies upon a flow rate of an oxygen gas, the oxygen gas is added to the etching gas so as to increase the etching rate of the nitride layer. As a result, a new etching gas has a ratio of 1:2.6:30:1.3 in CHF3, CF4, Ar and O2, and thereby it becomes possible for the oxide etching apparatus to etch the nitride layer. Furthermore, if the method is applied to a memory device, a fuse box and a pad can be etched at the same time.
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