Plasma etching is a powerful technique for transferring high-resolution lithographic masks into functional materials. Significant challenges arise with shrinking feature sizes, such as etching with thin masks. Traditionally this has been addressed with hard masks and consequently additional costly steps.
View Article and Find Full Text PDFPattern collapse of small or high aspect ratio lines during traditional wet development is a major challenge for miniaturization in nanolithography. Here we report on a new dry process which combines high resolution resist exposure with selective laser ablation to achieve high resolution with high aspect ratios. Using a low power 532 nm laser, we dry develop a normally negative tone methyl acetoxy calix(6)arene in positive tone to reveal sub-20 nm half-pitch features in a ∼100 nm film at aspect ratios unattainable with conventional development with ablation time of 1-2 s per laser pixel (∼600 nm diameter spot).
View Article and Find Full Text PDFReliable measurement of electrical charge transport in molecular layers is a delicate task that requires establishing contacts with electrodes without perturbing the molecular structure of the film. We show how this can be achieved by means of novel device consisting of ultra-flat electrodes separated by insulating material to support the molecular film. We show the fabrication process of these electrodes using a replica technique where gold electrodes are embedded in a silicon oxide film deposited on the angstrom-level flat surface of a silicon wafer.
View Article and Find Full Text PDFDirected self-assembly (DSA) of block copolymers (BCPs), either by selective wetting of surface chemical prepatterns or by graphoepitaxial alignment with surface topography, has ushered in a new era for high-resolution nanopatterning. These pioneering approaches, while effective, require expensive and time-consuming lithographic patterning of each substrate to direct the assembly. To overcome this shortcoming, nanoimprint molds--attainable via low-cost optical lithography--were investigated for their potential to be reusable and efficiently template the assembly of block copolymers (BCPs) while under complete confinement.
View Article and Find Full Text PDFResistive-switching memory (RRAM) is an emerging nanoscale device based on the localized metal-insulator transition within a few-nanometer-sized metal oxide region. RRAM is one of the most promising memory technologies for the ultimate downscaling of nonvolatile memory. However, to develop memory arrays with densities approaching 1 Tb cm(-2) , bottom-up schemes based on synthesis and assembly of metal oxide nanowires (NWs) must be demonstrated.
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