Formation of Native Surface Films

The surface profile of a copper line formed by CMP in a sluny of 1 vol% NH4OH plus alumina abrasive using a Suba IV pad. 

CujO forms and therefore is expected to be the surface film on the copper in the low regions where mechanical abrasion is absent. 

From the XPS data, it is still not clear if the CujFeCClSOg is present on the copper surface during polishing or if it forms immediately after polishing before the slurry is rinsed off from the 

In low pH oxidizing solutions, copper is not expected to form a surface film. The copper corrosion potential measured in 1 vol% HNO3 is 100 mVsHE- At a pH of 1 and a potential of 100 

Polish Rate and Etch Rate in NH4OH Slurries 

---