US 6,274,483 B1 · Method to improve metal line adhesion by trench corner shape modification

Abstract

A new method is provided for the creation of the trenches or line patterns of damascene structures. Under the first embodiment of the invention, the trenches that are created for the copper interconnect lines are sputter etched as a result of which the corners of the trenches around the top elevation of the trenches are rounded. Under the second embodiment of the invention a disposable hard mask is created over the surface of the dielectric after which the trenches for the interconnect lines are created. The surface of the hard mask layer including the created trenches are rf sputter etched resulting in a sharp reduction of the angle of incidence between sidewalls of the trenches around the perimeter of the trenches and the surface of the layer of dielectric. The barrier and seed layers are deposited over the surface of the disposable hard mask including the created trenches, the deposited copper is polished down to the surface of the dielectric.

Claims13

Dependent claims

A method of creating interconnecting conductive lines and conductive vias in a layer of insulating material, comprising the steps of:

providing a semiconductor substrate;
depositing a layer of dielectric over a surface of said substrate;
planarizing a surface of said layer of dielectric;
creating trenches or openings in said layer of dielectric for deposition of metal thereby creating a pattern of interconnect lines or interconnect vias;
sputter etching said created trenches or openings thereby faceting sidewalls of said trenches or openings by developing an ever-increasing facet or incline of sidewalls of said trenches or openings;
depositing a barrier layer over a surface of said layer of dielectric thereby including inside surfaces of said trenches or openings;
depositing a seed layer over a surface of said barrier layer;
depositing a layer of copper over a surface of said seed layer;
and
polishing said layer of copper thereby forming a pattern of interconnect lines or interconnect vias.

7 more elements

A method of creating interconnecting conductive lines and conductive vias in a layer of insulating material, comprising the steps of:

providing a semiconductor substrate;
depositing a layer of dielectric over a surface of said substrate;
planarizing a surface of said layer of dielectric;
depositing a sacrificial hard mask layer over a surface of said layer of dielectric;
patterning and etching said hard mask layer thereby creating openings in said hard mask said openings to have a pattern that coincides with a pattern of said interconnecting conductive lines and conductive vias that are to be created in said layer of dielectric;
creating trenches or openings in said layer of dielectric for deposition of metal thereby creating a pattern of interconnecting conductive lines and conductive vias;
sputter etching said created trenches or openings thereby faceting sidewalls of said trenches or openings by developing an ever-increasing facet or incline of sidewalls of said trenches or openings;
depositing a barrier layer over a surface of said hard mask layer thereby including inside surfaces of said pattern of interconnecting conductive lines and conductive vias;
depositing a seed layer over a surface of said barrier layer;
depositing a layer of copper over a surface of said seed layer;
and
polishing said layer of copper thereby forming a pattern of interconnecting conductive lines and conductive vias.

9 more elements

Dependencies are inferred from the claim text.

Method to improve metal line adhesion by trench corner shape modification

Life of this patent

Method to improve metal line adhesion by trench corner shape modification

Life of this patent

Abstract

Claims13