Method for forming a T-shaped plug having increased contact area
AssigneeTaiwan Semiconductor Manufacturing Company, Ltd.
InventorChingfu Lin
Life of this patent
Estimating the term…
Abstract
A method for forming a T-shaped contact plug is disclosed. A first insulating layer is formed atop of a substrate. A second insulating layer is then formed atop of the first insulating layer. The first and second insulating layers are patterned and etched to form a contact opening to the substrate. A portion of the second insulating layer surrounding the contact opening is removed. Next, a barrier metal layer is formed along the walls of the contact opening and atop the second insulating layer. Then a conducting layer is formed into the contact opening and atop the barrier metal layer. Finally, a portion of the first conducting layer and barrier metal layer atop the second insulating layer is removed. This leaves a plug formed of the remaining portion of the conducting layer.
Claims10
A method for forming a plug on a semiconductor substrate, the method comprising:
- forming an oxide layer atop said semiconductor substrate;
- forming a nitride layer atop said first insulating layer;
- patterning and etching said first insulating layer and said second insulating layer, stopping at said semiconductor substrate, to form a contact opening;
- removing a portion of said second insulating layer that immediately surrounds the periphery of said contact opening using an isotropic etch;
- forming a barrier metal layer along the walls of said contact opening and atop said second insulating layer;
- forming a first conducting layer into said contact opening and atop said barrier metal layer;
- and
- removing a portion of said first conducting layer and said barrier metal layer atop said second insulating layer, leaving a plug formed of the remaining portion of said first conducting layer.
A method for forming a plug on a semiconductor substrate, the method comprising:
- forming an oxide layer atop said semiconductor substrate;
- forming a nitride layer atop said first insulating layer;
- patterning and etching said first insulating layer and said second insulating layer, stopping at said semiconductor substrate, to form a contact opening;
- removing a portion of said second insulating layer surrounding said contact opening using an isotropic etch, said removal being done substantially uniformly around the periphery of said contact opening;
- forming a barrier metal layer along the walls of said contact opening and atop said second insulating layer;
- forming a first conducting layer into said contact opening and atop said barrier metal layer;
- and
- removing a portion of said first conducting layer and said barrier metal layer atop said second insulating layer, leaving a plug formed of the remaining portion of said first conducting layer.
Dependencies are inferred from the claim text.