Fast Ultrahigh-Density Writing of Low Conductivity Patterns on Semiconducting Polymers

The exceptional interest in improving the limitations of data storage, molecular electronics, and optoelectronics has promoted the development of an ever increasing number of techniques used to pattern polymers at micro and nanoscale. Most of them rely on Atomic Force Microscopy to thermally or electrostatically induce mass transport, thereby creating topographic features. Here we show that the mechanical interaction of the tip of the Atomic Force Microscope with the surface of a class of conjugate polymers produces a local increase of molecular disorder, inducing a localized lowering of the semiconductor conductivity, not associated to detectable modifications in the surface topography. This phenomenon allows for the swift production of low conductivity patterns on the polymer surface at an unprecedented speed exceeding 20 $\mu m s^{-1}$; paths have a resolution in the order of the tip size (20 nm) and are detected by a Conducting-Atomic Force Microscopy tip in the conductivity maps.Comment: 22 pages, 6 figures, published in Nature Communications as Article (8 pages

Surface-directed dewetting of a block copolymer for fabricating highly uniform nanostructured microdroplets and concentric nanorings

Through a combination of nanoimprint lithography and block copolymer self-assembly, a highly regular dewetting process of a symmetric diblock copolymer occurs whereby the hierarchal formation of microdroplets and concentric nanorings emerges. The process is driven by the unique chemical properties and geometrical layout of the underlying patterned silsesquioxane micrometer-sized templates. Given the presence of nonpreferential substrate−polymer interactions, directed dewetting was utilized to produce uniform arrays of microsized droplets of microphase separated polystyrene-block-poly(methyl methylacrylate) (PS-b-PMMA), following thermal annealing at 180 °C. Microdroplets with diameters greater than 400 nm exhibited a hexagonal close-packed arrangement of nanodots on the surface with polydomain ordering. At the droplet periphery, the polydomain ordering was severely disrupted because of a higher in-plane radius of curvature. By reducing the droplet size, the in-plane radius of curvature of the microdroplet becomes significant and the PMMA cylinders adopt parallel structures in this confined geometry. Continuous scaling of the droplet results in the generation of isolated, freestanding, self-aligned, and self-supported oblique nanorings (long axis ∼250−350 nm), which form as interstitial droplets between the larger microdroplets. Optical and magnetic-based nanostructures may benefit from such hierarchal organization and self-supporting/aligned nanoring templates by combining more than one lithography technique with different resolution capabilities

Hybrid materials - past, present and future

Hybrid materials represent one of the most growing new material classes at the edge of technological innovations. Unique possibilities to create novel material properties by synergetic combination of inorganic and organic components on the molecular scale makes this materials class interesting for application-oriented research of chemists, physicists, and materials scientists. The modular approach for combination of properties by the selection of the best suited components opens new options for the generation of materials that are able to solve many technological problems. This review will show in selected examples how science and technological driven approaches can help to design better materials for future applications

Applications of Hydrogen Silsesquioxane in Nanomanufacturing and Nanofabrication

Hydrogen silsesquioxane (HSQ) is a versatile inorganic material that has garnered significant attention in the semiconductor industry, such as in micro-/nano-electromechanical systems, photonic devices, and nanoelectronics, owing to its high silicon content, small molecular size, low dielectric constant, excellent line edge roughness, high etching resistance, and local planarization capabilities. This review article discusses the application-related aspects of HSQ in nanomanufacturing for integrated circuits and nanoscale patterning, and the technical applications of HSQ in the fabrication of semiconductor silicon-based nanomaterials.departmental bulletin pape

Cubic Silsesquioxanes as a Green, High-Performance Mold Material for Nanoimprint Lithography

No AbstractPeer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/78504/1/414_ftp.pd

Novel Organosilicone Materials and Patterning Techniques for Nanoimprint Lithography.

Nanoimprint Lithography (NIL) is a high-throughput patterning technique that allows the fabrication of nanostructures with great precision. It has been listed on the International Technology Roadmap for Semiconductors (ITRS) as a candidate technology for future generation Si chip manufacturing. In nanoimprint Lithography a resist material, e.g. a thermoplastic polymer, is placed in contact with a mold and then mechanically deformed under an applied load to transfer the nano-features on the mold surface into the resist. The success of NIL relies heavily in the capability of fabricating nanostructures on different types of materials. Thus, a key factor for NIL implementation in industrial settings is the development of advanced materials suitable as the nanoimprint resist. This dissertation focuses on the engineering of new polymer materials suitable as NIL resist. A variety of silicone-based polymer precursors were synthesized and formulated for NIL applications. High throughput and high yield nanopatterning was successfully achieved. Furthermore, additional capabilities of the developed materials were explored for a range of NIL applications such as their use as flexible, UV-transparent stamps and silicon compatible etching layers. Finally, new strategies were investigated to expand the NIL potentiality. High throughput, non-residual layer imprinting was achieved with the newly developed resist materials. In addition, several strategies were designed for the precise control of nanoscale size patterned structures with multifunctional resist systems by post-imprinting modification of the pattern size. These developments provide NIL with a new set of tools for a variety of additional important applications.Ph.D.Macromolecular Science & EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/64783/1/pinac_1.pd