Method for forming dual damascene structures
AssigneeMicron Technology, Inc.
InventorAllen McTeer
Life of this patent
Estimating the term…
Abstract
A method for forming Dual Damascene structures wherein a via is etched to an element to be contacted, a non-photoreactive protective layer is deposited in the via, and an intersecting trench is formed. The protective layer is then removed, together with any residual debris resulting from the trench formation. The protective layer enhances reliability of the electrical contact at the bottom of the via.
Claims30
A method for forming a recess in a substrate representing a semiconductor interconnect via and trough pattern, comprising:
- forming a layer of etchable material;
- removing a portion of said etchable material to form a via;
- forming a protective layer within and along the bottom of said via, said protective layer protecting said bottom of said via from debris;
- removing a portion of said etchable material to form a trough transverse to and intersecting an upper portion of said via;
- and
- removing from said via said protective layer and said debris.
A method for forming a contact to a semiconductor device feature, comprising the steps of:
- forming a dielectric layer over a feature to be contacted;
- forming a first layer of photoresist over said dielectric layer;
- patterning said first layer of photoresist and etching said dielectric layer to form a via through said dielectric to outwardly expose a contact surface of said device feature;
- forming a layer of non-photoreactive material within and along the bottom of said via and atop said outwardly exposed contact surface of said device feature, said non-photoreactive material protecting said bottom of said via from debris;
- forming a second layer of photoresist over said dielectric layer and non-photoreactive material;
- patterning said second layer of photoresist and etching said dielectric layer to form a trough intersecting the upper portion of said via;
- removing from said via said non-photoreactive layer and photoresist, and said debris;
- forming a conductive layer within said via and trough and in contact with said outwardly exposed contact surface of said device feature.
A method for forming a semiconductor via contact and trough interconnect to an underlying substrate, comprising:
- forming a first layer of electrically insulative material on an electrically conductive material of an underlying substrate;
- etching a portion of said insulative material to form a via and outwardly exposing a portion of said electrically conductive material;
- forming a protective coating within and along the bottom of said via and atop said exposed portion of electrically conductive material, said coating protecting said bottom of said via from debris;
- applying a selective etch to remove a portion of said etchable material to form a trough transverse to and intersecting an upper portion of said via and removing a portion of said protective coating;
- removing from said via the remaining portion of said protective coating and photoresist, and said debris;
- and
- applying a conductive material to fill said via and trough.
Dependencies are inferred from the claim text.