Patent ID: 6110826
Filing Date: 2000-08-29
Classification: H01L

Abstract:
A method of forming a dual damascene structure using selective tungsten chemical vapor deposition comprising the steps of:providing a semiconductor substrate having active and passive regions;forming an interlevel dielectric (ILD) layer over said substrate having active and passive regions;forming an etch-stop layer over said ILD layer;forming an intermetal dielectric (IMD) layer over said etch-stop layer;forming a first photoresist layer over said IMD layer and patterning said photoresist layer with a mask comprising a line trench pattern;etching through said line trench pattern in said first photoresist layer to form said line trench pattern into said IMD layer, wherein said line trench has a sidewall and a flat bottom;removing said first photoresist layer;forming a seed layer over said IMD layer including said line trench with said sidewall and said flat bottom;removing said seed layer from the surface of said IMD layer including said flat bottom of said line trench;forming a second photoresist layer over said IMD layer and said line trench having sidewalls covered with said seed layer;patterning said second photoresist layer with a mask comprising a contact hole pattern;etching through said contact hole pattern in said second photoresist layer to form said contact hole pattern into said interlevel dielectric (ILD) layer;removing said second photoresist layer;cleaning said contact hole;depositing selective W CVD in said line trench and said contact hole composite structure; andperforming chemical mechanical polish to planarize said substrate for subsequent process steps to complete the fabrication of a semiconductor substrate.