Stamping Lithography

An experiment that demonstrates stamping lithography, a process which may substitute photolithographic printing in microelectronics is described. A stamp is created by curing polydimethylsiloxane (PDMS) on a patterned template, and a glass slide coated with Ag using electroless plating. The stamp is then inked with 5 mM of undecanethiol in ethanol, dried and brought into brief contact with the Ag. Thiol molecules transfer instantaneously onto the Ag, forming patterns of self assembled monolayer (SAM) of undecanethiol which replicate raised features on the stamp. A ferrocyanide/ferricyanide solution is used to etch portions of the Ag that are not protected by the SAM, resulting in a pattern on the glass that is a replica of the original template.