LASER-ASSISTED PD SEEDING FOR ELECTROLESS PLATING ON SIO2

Excimer laser pulses with wavelengths of 248 and 308 nm were used to s electively seed Pd on SiO2 surfaces, making them suitable for electrol ess plating. This novel seeding process for insulating materials is ac complished with the sample immersed in the seeding solution, and occur s only on the areas of the substrate that are illuminated (through the liquid) by the laser light. The Pd content of the seeded samples incr eased with the number of pulses, but was rather independent of repetit ion rate. The deposition rate showed a dependence with wavelength cons istent with a defect driven mechanism for electron excitation through the band gap of SiO2. These electrons then reduce the Pd ions in the s olution in contact with the surface.