Processes and Systems for Engineering a Barrier Surface for Copper Deposition

An integrated system for processing a substrate in controlled environment to enable selective deposition of a thin copper seed layer on a surface of a metallic barrier layer of a copper interconnect and preparing a planarized copper surface of the copper interconnect to selectively depositing a thin layer of a cobalt-alloy material in an integrated system to improve electromigration performance of the copper interconnect, comprising:

• a lab-ambient transfer chamber capable of transferring the substrate from a substrate cassette coupled to the lab-ambient transfer chamber into the integrated system;
• a vacuum transfer chamber operated under vacuum at a pressure less than 1 Torr, wherein at least one vacuum process module is coupled to the vacuum transfer chamber;
• an Ar sputtering process module to clean an exposed surface of a metal oxide of a underlying metal in the integrated system, wherein the underlying metal is part of a underlying interconnect, the copper interconnect is electrically connected to the underlying interconnect, the Ar sputtering process module one of the at least one vacuum process module is coupled to the vacuum transfer chamber;
• an atomic layer deposition (ALD) process module for depositing a thin first metallic barrier layer, wherein the ALD process module is one of the at least one vacuum process module coupled to the vacuum transfer chamber;
• a PVD process chamber for depositing a thin second metallic barrier layer, wherein the PVD process module is one of the at least one vacuum process module coupled to the vacuum transfer chamber;
• a hydrogen reduction process module for reducing a metal oxide or metal nitride to a metal, wherein the hydrogen reduction process module is one of the at least one vacuum process module coupled to the vacuum transfer chamber;
• an oxygen plasma process module for removing organic contaminants from the substrate surface, wherein the oxygen plasma process module is one of the at least one vacuum process module coupled to the vacuum transfer chamber;
• a controlled-ambient transfer chamber filled with an inert gas selected from a group of inert gases, wherein at least one controlled-ambient process module is coupled to the controlled-ambient transfer chamber;
• an electroless copper deposition process module used to deposit the thin layer of copper seed layer and a gap-fill copper layer on the surface of the metallic barrier layer, the electroless copper deposition process module being one of the at least one controlled-ambient process module coupled to the controlled-ambient transfer chamber;
• an electroless cobalt-alloy deposition process module used to deposit the thin layer of the cobalt-alloy material on the prepared planarized copper surface, the electroless copper alloy deposition process module being one of the at least one controlled-ambient process module coupled to the controlled-ambient transfer chamber;
• a planarizing process module used to remove a copper overburden and a bather overburden of the copper interconnect, the planarizing process module is one of the at least one controlled-ambient process module coupled to the controlled-ambient transfer module;
• and
• a wet clean process module used to remove metallic contamination on the substrate surface, the wet clean process module is one of the at least one controlled-ambient process module coupled to the controlled-ambient transfer module.

An integrated system for processing a substrate in controlled environment to enable deposition of a thin copper seed layer on a surface of a metallic barrier layer of a copper interconnect, comprising:

• a lab-ambient transfer chamber capable of transferring the substrate from a substrate cassette coupled to the lab-ambient transfer chamber into the integrated system;
• a vacuum transfer chamber operated under vacuum at a pressure less than 1 Torr, wherein at least one vacuum process module is coupled to the vacuum transfer chamber;
• a vacuum process module for reducing the metallic barrier layer, wherein the vacuum process module for reducing the metallic barrier layer one of the at least one vacuum process module is coupled to the vacuum transfer chamber, and is operated under vacuum at a pressure less than 1 Torr;
• a controlled-ambient transfer chamber filled with an inert gas selected from a group of inert gases, wherein at least one controlled-ambient process module is coupled to the controlled-ambient transfer chamber;
• and
• an electroless copper deposition process module used to deposit the thin layer of copper seed layer on the surface of the metallic barrier layer, wherein the electroless copper deposition process module is one of the at least one controlled environment process modules coupled to the controlled-ambient transfer chamber.