Formation and use of palladium(II)–thiol complexes at the surface of PDMS stamps for the fabrication of high resolution and high density metal patterns using soft-lithography techniques

Palladium(II)–thiol complexes were synthetized at the surface of patterned PDMS stamps and were transferred onto the surface of numerous substrates using microcontact printing (μCP) and submerged microcontact printing (SμCP). These complexes were used for the fabrication of micro- and nano-scale metal patterns following both top-down and bottom-up processes. For top-down processes, palladium(II)–thiol complexes were used as mask for wet chemical etching. For bottom-up processes, palladium(II)–thiol complexes were transferred onto silanized silicon wafers and plasma-treated polymers. Plasma post-treatments under reducing conditions led to palladium nanoparticles down to 10 nm in diameter. These nanoparticles were then used as catalysts for the electroless deposition of copper or nickel patterns. Patterns of 200 nm wide metal dots (high resolution) with a period of 400 nm (high density) can be obtained.