Slurry Development for Copper/Barrier CMP

Hebei University of Technology (abbreviated as HEBUT) has developed Cu/barrier CMP slurries for about two decades. Two slurries have been formulated for Cu CMP: (1) FA/O I and (2) FA/O II. Both of them are colloidal silica based alkaline slurries. In FA/O I, there is alkali additive of R(NH2)(OH) as the complex agent. In FA/O II, there is also an alkali additive of R(NH2)2 as the complex agent. The pH of FA/O II is higher than that of FA/O I, however. FA/O I slurry can be directly used for barrier polish, and it can also be used for 2nd step Cu CMP after a certain amount of H2O2 is mixed. F A/O II slurry can be used for 1st step Cu CMP with addition of H2O2.