Multi-layer wirings on a semiconductor device and fabrication method

Claim 1

A semiconductor device comprising: a first wiring formed of an electrically conductive material which is soluble in a solution containing hydrofluoric acid, said first wiring being insulatingly arranged upon a semiconductor substrate; a first insulating layer formed on said first wiring; a second wiring formed of an electrically conductive material, arranged insulatingly from said first wiring, said second wiring overlies said first wiring via said first insulating layer; a second insulating layer formed under said first wiring; and a third wiring, formed of an electrically conductive material being resistant to a solution containing hydrofluoric acid, said third wiring electrically connecting said first wiring and said second wiring, a first part of said third wiring underlies said first wiring via said second insulating layer and is connected to said first wiring through a plurality of first contact holes provided through said second insulating layer at a predetermined spacing therebetween along said first wiring, a second part of said third wiring, which extends from said first part, is connected to said second wiring through a second contact hole provided through said first and second insulating layers.