TUNGSTEN PLUG MANUFACTURING METHOD

摘要

forming a first insulating layer (2) on a first conducting layer (1),a second metal wire (3) and a second insulating layer (4); forming a first contact hole (5) where the first conducting layer is revealed deep and wide and forming a second contact hole (6) where the second metal wire is revealed shallow and narrow by etching some part of the second insulating layer; depositing a blanket tungsten film (7) over the whole wafer to fill the second contact hole; depositing a polysilicon layer (10) over the tungsten film; forming plugs (11,12) in the second and the first contact hole by etching the polysilicon layer and the tungsten film until the top of the second insulating layer is revealed.