9. Stamping Techniques for Micro- and Nanofabrication

Soft-lithographic techniques that use rubber stamps and molds provide simple means to generate patterns with lateral dimensions that can be much smaller than one micron and can even extend into the single nanometer regime. These methods rely on the use of soft elastomeric elements typically made out of the polymer poly(dimethylsiloxane). The first section of this chapter presents the fabrication techniques for these elements together with data and experiments that provide insights into the fundamental resolution limits. Next, several representative soft-lithography techniques based on the use of these elements are presented: (i) microcontact printing, which uses molecular ‘inks’ that form self-assembled monolayers, (ii) near- and proximity-field photolithography for producing two- and three-dimensional structures with subwavelength resolution features, and (iii) nano-transfer printing, where soft or hard stamps print single or multiple layers of solid inks with feature sizes down to 100 nm. The chapter concludes with descriptions of some device-level applications that highlight the patterning capabilities and potential commercial uses of these techniques.