Effect of additive triblock copolymer PEP-3100 on bottom-up filling in electroless copper plating

Abstract

Bottom-up copper filling for different sub-micrometer trenches was investigated by electroless deposition technique using a PO-EO-PO triblock copolymer termed PEP-3100 as an additive. It was found that PEP-3100 (molecular weight 3100) had a strong inhibition for the electroless copper deposition. The bottom-up filling behavior of electroless copper bath for different trenches was investigated in a plating bath containing 1.0 mg l−1 PEP-3100. The cross-section SEM observation indicated the trenches with different widths ranging from 100 to 380 nm were all filled completely by electroless copper.