| 摘要 |
PROBLEM TO BE SOLVED: To realize constant working by suppressing variation in depth of a wiring groove in a wafer surface when forming a wiring structure. SOLUTION: When formed by dry etching in a laminate structure comprising a high carbon concentration insulating film 114 and a low carbon concentration insulating film 116 containing no carbon or having a low carbon concentration, the groove is formed in the low carbon concentration insulating film 116 under a first etching condition using a first etching gas to which a CHF-based gas is added, and then a high carbon concentration insulating film 114 is exposed from a wiring groove bottom part. A partial pressure of the CHF-based gas in the first etching gas of the first etching condition is set in such a range as an etching rate against the high carbon concentration insulating film 114 drops while that against the low carbon concentration insulating film 116 does not change, by adding the CHF-based gas with an etching rate relative to respective films when no CHF-based gas is added to the first etching gas as a reference. COPYRIGHT: (C)2011,JPO&INPIT
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