Patent ID: 6476488
Filing Date: 2002-11-05
Classification: H01L

Abstract:
Polysilicon landing plugs and metal landing plugs with electrical interconnections for contacts on semiconductor integrated circuits comprised of:a semiconductor substrate having device areas of a first type and device areas of a second type, and having devices with Nâˆ’ doped contacts in said device areas of said first type, and having N+ and P+ doped contacts in said device areas of said second type; a conformal first etch-stop layer partially etched back to form sidewall spacers on said devices and to protect said device areas of said first type and said device areas of said second type; a planar insulating layer over said device areas; said planar insulating layer and said etch-stop layer having first openings self-aligned to said devices and said first openings over and to said Nâˆ’ doped contacts in said device areas of said first type; an N+ doped polysilicon layer on said planar insulating layer and in said first openings and contacting said Nâˆ’ contacts; said N+ doped polysilicon layer, said planar insulating layer, and said first etch-stop layer having second openings to said N+ and P+ contacts in said device areas of said second type; interconnecting lines formed from a barrier layer, a metal layer, and a second etch-stop layer and from said N+ doped polysilicon layer, and concurrently leaving said N+ doped polysilicon landing plugs in said device areas of said first type and leaving said metal layer in said N+ and said P+ contacts in said device areas of said second type to form said metal landing plugs.