PLASMA IMMERSION PD ION-IMPLANTATION SEEDING PATTERN-FORMATION FOR SELECTIVE ELECTROLESS CU PLATING

Selective plating of Cu for interconnects was carried out using plasma immersion Pd ion implantation and Cu electroless plating. Pd ions were sputtered from a negatively biased target and ionized in an Ar electron cyclotron resonance (ECR) plasma. The Pd ions were implanted into the SiO2 substrates biased with negative high pulsed voltages. In our studies, we found the required Pd seeding dose for Cu plating was on the order of 5 x 10(14)/cm2. With a direct Pd implantation, an intermediate activation step using a PdCl2 solution was eliminated.