Patent ID: 7119007

Claim:
A production method of a semiconductor device having an interlayer insulating film including an organic insulating film, said method comprising: (a) a step of forming said interlayer insulating film including said organic insulating film in which wiring is included, (b) a step of forming on the interlayer insulating film a first mask as an etching mask having an inverted pattern of wiring trenches for upper wiring, which is used when the interlayer insulating film undergoes etching through said first mask, thereby forming in the first mask a portion conforming to the inverted pattern of wiring trenches; and (c) a step of forming a second mask on said first mask as a second etching mask which is used to fabricate the interlayer insulating film and which is made of a material different from that of the first mask and is locally buried in the first mask, and (d) selectively modifying the first mask through an opening in the second mask by reactive ion etching of said first mask.