The use of self-assembled monolayers and a selective etch to generate patterned gold features

on the surface of the gold block this etching. Using a number of techniques-micromachining, microwriting, electron-beam lithography, ion-beam lithography-it is possible to form patterns of SAMs on the Au surface. By combining these techniques for forming patterns with selective etching using the CN-/O2 solution, high-resolution patterns of gold on silicon can be fabricated with dimensions as small as I pm.5 One procedure used a pen to write patterns of hexadecanethiolate6 as monolayers on Au substrates. The pen, filled with