By Melbourne Centre for Nanofabrication
Soft lithography is a process by which rigid master mold structures, typically silicon/SU8, are replicated in an elastomeric material known as polydimethylsiloxane (PDMS). Silicon is exposed to the desired pattern using photoresist, after which the patterned structure is treated with an anti-stick coating and liquid PDMS is poured over it. Once cured, "daughter" devices can be removed from the mold whose features match that of the master. Useful for its flexibility, PDMS is ideal in applications involving surfaces which are not flat. PDMS can also be used in microfluidic applications, where rapid prototyping is important. It is also biocompatible and oxygen permeable making it useful in a broad range of bio-applications, and it is optically transparent. MCN has a dedicated PDMS laboratory where staff use Sylgard 184 PDMS.
