Roll to Roll Nanoimprinting

In this phase 1 STTR, a roll-to-roll (R2R), high throughput nanoimprint lithography system and process prototype will be developed based on Molecular Imprints Inc."s Jet and Flash Imprint Lithography (J-FIL) technology. The R2R system will incorporate resist ink jetting with web tension control to achieve sub-50nm lithography and the following key process attributes: (i) Thin and uniform residual layer control with a target sub-15nm (mean) and sub-2nm (sigma); (ii) High aspect ratio patterns (>3:1 ratio) at 50nm resolution with arbitrary complexity; (iii) High throughput with target of>5m/min; and (iv) low resist material usage (~50-150 micro-liters/m2). The resulting process will allow pattern transfer into dielectrics and metal films with control in pattern size and complexity; and the cost structure will be attractive even for commodity applications such as thin-film solar cells. This process could be applied to applications such as large area sub-wavelength photonics devices, displays, and solar cells. We will focus on plasmonic nanostructures for thin-film solar cells based on amorphous silicon. We will perform simulation studies to obtain optimal plasmonic structures for maximizing absorption at long wavelengths over a broad band. We will then demonstrate fabrication (including pattern transfer) of these representative plasmonic patterns in appropriate film stacks.