Research on Nanoimprint Lithography

Nanoimprint Lithography (NIL) is a surface patterning technique that, in the recent literature, has been shown to provide resist linewidth resolutions down to about 5 nm.  A basic NIL process is shown in the schematic.  Essentially the surface pattern of a hard mold is replicated into a thermoplastic resist material at elevated temperature and pressure.  Alternative resist materials, such as UV-sensitive precursor resins, can also be employed.  Given an optically transparent mold, pattern replication can be achieved by exposing the precursor to UV light through the mold under elevated pressure.  This imprinting mode is often referred to as UV-NIL. 

Compared to other nanofabrication techniques such as e-beam lithography, x-ray lithography, and immersion-assisted photolithography, NIL benefits from higher throughput and lower capital equipment start-up costs.  Furthermore, the NIL process is very flexible.  It can accommodate a large variety of polymeric materials and commercially available resists.  It is also compatible with either stiff or flexible substrate materials particularly silicon, glass, metal sheets and films as well as plastics.  The many advantages of NIL make it well-disposed towards the fabrication of semiconductors, micro- and nano-electro-mechanical devices, optical components and biological or chemical templates.