Method for forming a metal plug
AssigneeUnited Microelectronics Corp.
InventorsKun-Lin Wu, Horng-Bor Lu
Life of this patent
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Abstract
A method for forming a metal plug is provided. The method is used to form a metal plug without a hole on a glue/barrier layer within a trench when the glue/barrier layer has been formed for a while. A substrate with a trench therein and a glue/barrier layer formed conformal to the profile of the substrate is provided. A post-treatment is performed on the glue/barrier layer to prevent moisture absorption and to make the glue/barrier become dense. The post-treatment comprises a plasma treatment or a deep UV plus laser treatment. After performing the post-treatment step, a metal layer is formed on the glue/barrier layer at least to fill in the trench. The metal layer other than that filling the trench is removed to form a metal plug.
Claims20
A method for forming a metal plug, comprising the steps of:
- providing a substrate comprising a trench therein and a titanium nitride layer formed along the profile of the substrate;
- performing a plasma treatment to the titanium nitride layer;
- performing a post-treatment comprising a plasma or a deep UV laser on the titanium nitride layer after exposing the titanium nitride layer in air for a period of time, so as to make the titanium nitride dense and to increase the adhesion of the titanium nitride layer for attaching a metal layer thereon in a subsequent step;
- forming the metal layer on the titanium nitride layer at least to fill the trench;
- removing a part of the metal layer other than that filling the trench.
A method for forming a metal layer is performed after a period of time while a glue/barrier layer has been formed on a substrate and exposed in air, the method comprising the steps of:
- performing a plasma treatment on the glue/barrier layer;
- performing a post-treatment on the glue/barrier layer after the plasma treatment;
- forming the metal layer on the glue/barrier layer.
Dependencies are inferred from the claim text.