Precision patterned optical films are key components of today's display technologies, serving as brightness enhancement
films, diffuser films and patterned light guides, to name a few. In recent years, much attention has been given to
methodologies for patterning optical films with nanoscale precision at the scale and economics required by the Flat Panel
Display industry. With this work, we report a platform technology, Pattern Replication In Non-Wetting Templates
(PRINT®), for polymer-tool based manufacturing of patterned optical films for the display industry. By using Fluorocur®
mold materials, the PRINT® (Pattern Replication In Nonwetting Template) technology enables low cost manufacturing
of precise micro and nanoscale features with single nanometer precision from virtually any material.
The delivery of therapeutic, detection and imaging agents for the diagnosis and treatment of cancer patients has improved dramatically over the years with the development of nano-carriers such as liposomes, micelles, dendrimers, biomolecules, polymer particles, and colloidal precipitates. While many of these carriers have been used with great success in vitro and in vivo, each suffers from serious drawbacks with regard to stability, flexibility, or functionality. To date, there has been no general particle fabrication method available that afforded rigorous control over particle size, shape, composition, cargo and chemical structure. By utilizing the method we has designed referred to as Particle Replication In Non-wetting Templates, or PRINT, we can fabricate monodisperse particles with simultaneous control over structure (i.e. shape, size, composition) and function (i.e. cargo, surface structure). Unlike other particle fabrication techniques, PRINT is delicate and general enough to be compatible with a variety of important next-generation cancer therapeutic, detection and imaging agents, including various cargos (e.g. DNA, proteins, chemotherapy drugs, biosensor dyes, radio-markers, contrast agents), targeting ligands (e.g. antibodies, cell targeting peptides) and functional matrix materials (e.g. bioabsorbable polymers or stimuli responsive matrices). PRINT makes this possible by utilizing low-surface energy, chemically resistant fluoropolymers as molding materials and patterned substrates to produce functional, harvestable, monodisperse polymeric particles.
We describe the use of multifunctional perfluoropolyethers as enabling materials in imprint lithography and metrology. Perfluoropolyethers (PFPEs) are a unique class of fluoropolymers that are liquids at room temperature that can be functionalized and cured to form transparent "PTFE-like" elastomers. These materials posses many favorable attributes relative to imprint lithography and other soft lithographic techniques including: chemical resistance, flexibility, incredibly low surface energies, high gas permeability, and UV transparency. Molds made from PFPE materials exhibit the favorable properties of both rigid and soft materials in that they are rapidly made and disposable, yet maintain the chemical resistance and performance of rigid materials such as quartz. We have previously demonstrated the use of such materials in patterning 70nm features with a precision of +/-1 nm. Herein, we further demonstrate the capability of these materials in the rapid patterning of dual damascene structures and other patterns. The chemical resistance of PFPE-based materials allows for the patterning of a variety of organic resins including etch resists, low-k dielectrics, and conducting polymers. Additionally, we demonstrate the utility of functional PFPEs in a novel metrology method. In this simple technique, the liquid PFPE precursor is poured onto a wafer with a given pattern and cured. When released from the wafer, the cured film possesses an exact negative replica of the original pattern. A variety of metrology and inspection methods can then be performed on the patterned, transparent film including microscopy and through-film optics which can reveal defects in the original pattern. Furthermore, the method is shown to be completely non-destructive to the original patterned wafer. We describe the use of this method in the metrology and inspection of a dual damascene pattern containing features which are difficult to characterize by other techniques.