Cu and barrier removal peculiarities were studied and a differential multislurry (DMS) chemical mechanical planarization (CM) process for dual damascene technology was developed. Process shows Cu removal rates up to 1.2 mu m/min with an average nonuniformity <5%. Annealing was shown to have impact on process stability. Details of Cu removal mechanism were studied. Cu removal process was found to be temperature insensitive and following Preston＇s law that indicates its pseudo-mechanical nature. Abrasive enhancement of chemical activity was shown to be important for Cu removal. Phenomenon of metal feature thinning (MT) and dielectric erosion (DE) in heterogeneous CMP was analyzed and compared with data obtained fur various conditions. It was shown that properties of all major acting CMP characters: the tool (loading), the slurry (selectivity), and the pad (hardness) are contributing to MT. Hard pad, slurry selectivity less than or equal to 1 in the end of Cu clearance phase and low polishing pressure help to minimize MT. Some MT and DE related process integration issues are discussed, as well.