| abstract |
The present invention relates to a method of protecting a fresh metal surface, preferably copper, after a metal deposition step. The metal deposition is preferably part of single or dual damascene process. The metal surface is treated with an amine, preferably BTA, to form a metal complex that is a hydrophobic monolayer and prevents the underlying metal from reacting to form oxides that can degrade device performance. The amine can be applied in various ways including dipping, spraying, spin coating, and by a CVD method. The sacrificial protective layer can remain on the substrate during a storage period of up to hours or days before it is removed in a subsequent chemical mechanical polish step. The use of a sacrificial protective layer improves throughput in a damascene process by allowing long queue times between metal deposition and CMP which gives more flexibility to production flow and reduces cost. |