| 摘要 |
A method is provided for cleaning exposed copper surfaces in damascene structures after chemical mechanical polishing of the copper. In a first embodiment exposed copper is annealed in a forming gas environment, a mixture of hydrogen and nitrogen, after chemical mechanical polishing, or other etching means, is used to remove the copper down to the top of the trench dielectric. A layer of silicon nitride, SiN, is then immediately deposited, preferably in situ, over the exposed copper. In a second embodiment exposed copper is subjected to a plasma of NH3 after chemical mechanical polishing, or other etching means, is used to remove the copper down to the top of the trench dielectric. A layer of silicon nitride, SiN, is then immediately deposited in situ over the exposed copper. A layer of dielectric can then be deposited on the layer of silicon nitride and processing can be continued without contaminating or oxidizing the copper.
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