After accumulating a BPSG film layer on a silicon substrate, a first Al--Si--Cu film layer, a W film layer and a second Al--Si--Cu film layer are successively accumulated on this BPSG film layer. A resist pattern with wide-width and narrow-width pattern portions is formed on the second Al--Si--Cu film...http://www.google.es/patents/US5385867?utm_source=gb-gplus-sharePatente US5385867 - Method for forming a multi-layer metallic wiring structure
Method for forming a multi-layer metallic wiring structure
