A new plasma-enhanced co-polymerization (PCP) technology for reinforcing mechanical properties of organic silica low-k/Cu interconnects on 300 mm wafers

A new plasma-enhanced co-polymerization (PCP) technology is developed for low-k/Cu damascene integration on 300 mm wafers. The concept of the PCP technology is to introduce monomers, which have different functions such as matrix formation, deposition acceleration, or reinforcement, into a reactor exited with a He-plasma. It is shown that the low-k film growth rate from the matrix monomer such as divinyl siloxane-benzocyclobutene (DVS-BCB) and the elastic modulus of the deposited films are enhanced by adding a deposition acceleration monomer and a reinforcement monomer, respectively, without increasing the k-value. Combining the PCP technology with an ultra-low-pressure CMP technique, the Cu damascene interconnects were successfully fabricated on 300 mm wafers.