High aspect ratio electroplated metal feature and method
First Claim
1. A method of forming a metal structure comprising:
- forming an opening through a dielectric layer to a substrate;
lining said opening with a metal-plating seed layer;
forming a protective layer on said metal-plating seed layer;
removing said protective layer from a bottom surface of said opening; and
performing an electroplating process to fill said opening with an electroplated layer comprising one of a metal and a metal alloy,wherein said protective layer on sidewalls of said opening comprises a material pre-selected to have a metal-plating over-potential sufficient to selectively prevent electroplating of said one of said metal and said metal alloy, and an exposed portion of said metal-plating seed layer at said bottom surface of said opening promotes electroplating of said one of said metal and said metal alloy such that said electroplating process fills said opening with said electroplated layer from said bottom surface up.
3 Assignments
0 Petitions
Accused Products
Abstract
Disclosed are embodiments of an improved high aspect ratio electroplated metal structure (e.g., a copper or copper alloy interconnect, such as a back end of the line (BEOL) or middle of the line (MOL) contact) in which the electroplated metal fill material is free from seams and/or voids. Also, disclosed are embodiments of a method of forming such an electroplated metal structure by lining a high aspect ratio opening (e.g., a high aspect ratio via or trench) with a metal-plating seed layer and, then, forming a protective layer over the portion of the metal-plating seed layer adjacent to the opening sidewalls so that subsequent electroplating occurs only from the bottom surface of the opening up.
-
Citations
22 Claims
-
1. A method of forming a metal structure comprising:
-
forming an opening through a dielectric layer to a substrate; lining said opening with a metal-plating seed layer; forming a protective layer on said metal-plating seed layer; removing said protective layer from a bottom surface of said opening; and performing an electroplating process to fill said opening with an electroplated layer comprising one of a metal and a metal alloy, wherein said protective layer on sidewalls of said opening comprises a material pre-selected to have a metal-plating over-potential sufficient to selectively prevent electroplating of said one of said metal and said metal alloy, and an exposed portion of said metal-plating seed layer at said bottom surface of said opening promotes electroplating of said one of said metal and said metal alloy such that said electroplating process fills said opening with said electroplated layer from said bottom surface up. - View Dependent Claims (2, 5, 12, 13, 14, 15)
-
-
3. A method of forming a metal structure comprising:
-
forming an opening through a dielectric layer to a substrate; lining said opening with a metal-plating seed layer; forming a protective layer on said metal-plating seed layer; removing said protective layer from a bottom surface of said opening; and performing an electroplating process to fill said opening with an electroplated layer comprising one of a metal and a metal alloy, wherein said protective layer on sidewalls of said opening prevents electroplating of said one of said metal and said metal alloy, and an exposed portion of said metal-plating seed layer at said bottom surface of said opening promotes electroplating of said one of said metal and said metal alloy such that said electroplating process fills said opening with said electroplated layer from said bottom surface up, and wherein said forming of said protective layer comprises depositing a conformal additional metal layer over said metal-plating seed layer, wherein said additional metal layer is pre-selected to selectively prevent electroplating of said one of said metal and said metal alloy. - View Dependent Claims (16, 17)
-
-
4. A method of forming a metal structure comprising:
-
forming an opening through a dielectric layer to a substrate; lining said opening with a metal-plating seed layer; forming a protective layer on said metal-plating seed layer; removing said protective layer from a bottom surface of said opening; and performing an electroplating process to fill said opening with an electroplated layer comprising one of a metal and a metal alloy, wherein said protective layer on sidewalls of said opening prevents electroplating of said one of said metal and said metal alloy, and an exposed portion of said metal-plating seed layer at said bottom surface of said opening promotes electroplating of said one of said metal and said metal alloy such that said electroplating process fills said opening with said electroplated layer from said bottom surface up, and wherein said forming of said protective layer comprises depositing a conformal additional dielectric layer, wherein said additional dielectric layer is pre-selected to selectively prevent electroplating of said one of said metal and said metal alloy. - View Dependent Claims (18, 19)
-
-
6. A method of forming an interconnect structure, said method comprising:
-
forming an opening through a dielectric layer to a substrate; lining said opening with a copper-plating seed layer; forming a protective layer on said copper-plating seed layer; removing said protective layer from a bottom surface of said opening; and performing an electroplating process to fill said opening with an electroplated layer comprising one of copper and a copper alloy, wherein said protective layer on sidewalls of said opening prevents electroplating of said one of said copper and said copper alloy, and an exposed portion of said copper-plating seed layer at said bottom surface of said opening promotes electroplating of said one of said copper and said copper alloy such that said electroplating process fills with said opening with said electroplated layer from said bottom surface up, and wherein said forming of said protective layer comprises depositing a conformal layer of one of a metal and a metal alloy having a copper-plating over-potential sufficient to selectively prevent electroplating of said one of said copper and said copper alloy - View Dependent Claims (7, 8, 10, 11)
-
-
9. A method of forming an interconnect structure, said method comprising:
-
forming an opening through a dielectric layer to a substrate; lining said opening with a copper-plating seed layer; forming a protective layer on said copper-plating seed layer; removing said protective layer from a bottom surface of said opening; and performing an electroplating process to fill said opening with an electroplated layer comprising one of copper and a copper alloy, wherein said protective layer on sidewalls of said opening prevents electroplating of said one of said copper and said copper alloy, and an exposed portion of said copper-plating seed layer at said bottom surface of said opening promotes electroplating of said one of said copper and said copper alloy such that said electroplating process fills with said opening with said electroplated layer from said bottom surface up, and wherein said forming of said protective layer comprises depositing a conformal layer of a dielectric having a copper-plating over-potential sufficient to selectively prevent electroplating of said one of said copper and said copper alloy. - View Dependent Claims (20, 21, 22)
-
Specification