Integrated circuit prepared by selectively cleaning copper substrates, in-situ, to remove copper oxides

摘要

A system and method of selectively etching copper surfaces free of copper oxides in preparation for the deposition of an interconnecting metallic material is provided The method removes metal oxides with beta-diketones, such as Hhfac. The Hhfac is delivered into the system in vapor form, and reacts almost exclusively to copper oxides. The by-products of the cleaning process are likewise volatile for removal from the system with a vacuum pressure. Since the process is easily adaptable to most IC process systems, it can be conducted in an oxygen-free environment, without the removal of the IC from the process chamber. The in-situ cleaning process permits a minimum amount of copper oxide to reform before the deposition of the overlying interconnection metal. In this manner, a highly conductive electrical interconnection between the copper surface and the interconnecting metal material is formed. An IC having a metal interconnection, in which the underlying copper layer is cleaned of copper oxides, in-situ with Hhfac vapor, is also provided.