Browse Prior Art Database

A Method and Structure for Smooth Copper Seed Formation

IP.com Disclosure Number: IPCOM000198810D
Publication Date: 2010-Aug-17
Document File: 2 page(s) / 21K

Publishing Venue

The IP.com Prior Art Database

Abstract

Disclosed is a method of depositing an impurity such as Al and Mn before Chemical Vapor Deposition of copper (CVD-Cu) in order to enable smooth copper seed formation.

This text was extracted from a PDF file.
This is the abbreviated version, containing approximately 59% of the total text.

Page 1 of 2

A Method and Structure for Smooth Copper Seed Formation

A method of depositing an impurity such as Al and Mn before Chemical Vapor Deposition of copper (CVD-Cu) in order to enable smooth copper seed formation is disclosed.

CVD-Co) is widely used for step coverage which is required in modern Ultra Large Scale Integration (ULSI) interconnect fabrication processes. However, the morphology of the CVD-Co is rough thus making the CVD-Co impossible to be applied for formation of a copper seed layer or for copper gap filling in the fine trench and via patterns. Also, an interface between the underlying barrier layer and the CVD-Co contains oxygen, fluorine and carbon contamination which causes poor reliability performance and void formation.

The method disclosed herein includes, performing an impurity CVD with Al or Mn before depositing CVD-Cu in order to form a thin layer on top of liner materials such as, TaN, Ta, Co and Ru. Mn CVD forms an interface of liner and Mn in the structure. Since Mn is a strong oxygen getter, the liner surface is not oxidized during the deposition. When the CVD-Cu is performed on top of this Mn layer, intermixing of Mn and Cu takes place during the CVD-Cu. This helps in wetting the CVD-Cu layer to result in a smooth copper seed formation, thereby resolving the rough morphology problem.

Subsequently, a CVD of an alloy of Cu and Mn is performed. Cu and Mn are co-deposited in the CVD process. The incorporation of Mn helps in a smooth copper seed...