摘要 |
A wafer having an interlayer insulating film on a silicon substrate and an Al alloy layer on the interlayer insulating film coated with a resist pattern is introduced into an etching chamber where the Al alloy layer is selectively etched in etchant gas plasma. A main etching process is performed under the etching conditions of a high plasma density until the interlayer insulating film 12 is exposed, and a succeeding over etching process is performed under the etching conditions of a low plasma density. A dry etching method and system is provided which can suppress generation of an abnormal shape or notch of a wiring pattern etched in low pressure and high density plasma, without sacrificing etching selectivity and with productivity being maintained high.
|