Self-patterned seedless gold electroplating in high-aspect-ratio channels for μGC applications

This paper reports, for the first time, a new phenomenon named self-patterned electroplating used to selectively deposit a thin gold layer on vertical sidewalls of high-aspect-ratio channels. The ability to cover only vertical surfaces of three dimensional (3D) structures is a significant achievement in microsystems technology serving a wide range of applications including gas chromatography (GC). Self-patterned electroplating was used to deposit gold on the walls of microfabricated GC columns formed by deep reactive ion etching of silicon. The gold layer was then functionalized by self-assembly of thiols to form monolayer-protected-gold as the stationary phase coating. High uniformity, reproducibility, and separation capability are characteristics of these MPGs developed by merging MEMS and nanotechnology.