摘要 |
The present invention relates to a method for removing polysilicon layers used as a hard mask from contact holes without damaging the semiconductor substrate during the etching process. The present invention according to the present invention comprises the steps of: forming a nitride layer on a contact region to be contacted with a conducting layer; forming an interlayer insulation layer on the nitride layer, wherein the interlayer insulation layer has a different etching rate from the nitride layer so that the nitride layer acts as an etching barrier layer for the interlayer insulation layer; forming a polysilicon pattern on the interlayer insulation layer; etching the interlayer insulation layer using the polysilicon pattern as an etching mask, whereby a first opening to expose a portion of the nitride layer is formed; and etching the exposed nitride layer, thereby forming a second opening to expose the contact region.
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