Electroless Deposition of Cu on Glass and Patterning with Microcontact Printing

Electroless-depositing a metal from solution to a substrate and patterning it using microcontact printing is an alternative to the conventional patterning of vacuum-deposited metals using photolithography. Here, we pattern Cu onto 15 × 15 sq-inch glass substrates by (i) self-assembly of a thin layer of amino-derivatized silanes to the glass, (ii) binding Pd/Sn catalytic particles to the silanes, (iii) electroless deposition of ∼120 nm of Cu on the catalytic surface, (iv) microcontact printing hexadecanethiol on the Cu film using an accurate printing tool, and (v) selectively etching the printed Cu using hexadecanethiol as a resist. This method is particularly attractive for the fabrication of metallic gates for thin-film transistor liquid-crystal displays.