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1	Enabling scalability of Bio J-FIL process using intermediate adhesive layers in fabricating PEGDA based nanocarriers Marshall, Kervin Scott 01 November 2013 (has links) The Bio J-FIL process has been demonstrated to be a viable method for manufacturing nanoscale, polymeric drug carriers. The process allows for precise control of the size and shape of the drug carriers. While the original process is sufficient for research scale projects, reliability issues have prevented it from being scalable to levels that could potentially be used for mass-production of the drug carriers. In this thesis, a detailed root cause analysis has been conducted to determine the cause of the reliability issues limiting the Bio JFIL process. A series of experiments with varying substrate and imprint fluid combinations were conducted to pinpoint the cause of imprint failure in the Bio J-FIL process. Upon determining the cause of failure, an alternative imprint process was investigated that sought to increase the variety of materials used in the process by utilizing an intermediary layer. This process is referred to in this thesis as the Bio JFIL-I process. The results using Bio JFIL-I indicated increased reliability over the standard Bio J-FIL process. Further refinement of the Bio JFIL-I process could also address additional issues with the Bio J-FIL process unrelated to process reliability. The Bio JFIL-I approach presented in this thesis is complementary to other approaches that have been recently pursued in the literature which are discussed in the thesis. / text Nano manufacturing Polymeric drug carriers Soluble release layer J-FIL Imprint lithography
2	Nano-Manufacturing of Catalytic Amorphous Alloys Hasannaeimi, Vahid 12 1900 (has links) In this dissertation, nano-manufacturing of amorphous alloys for electro-catalytic applications is reported and the role of chemistry and active surface area on catalytic behavior is discussed. The catalytic activity of recently developed platinum and palladium-based metallic glasses was studied using cyclic voltammetry and localized electrochemical techniques. The synergistic effect between platinum and palladium was shown for amorphous alloys containing both these elements. The mechanism for superior catalytic behavior was investigated through electronic structure and surface chemical state of the alloys. A correlation between the work function and catalytic performance of the amorphous alloys with widely varying chemistries was established. To address the high cost associated with the noble-metal containing catalysts, the performance of non-noble Ni-P amorphous catalyst was evaluated for electro-catalysis. A facile pulsed electrodeposition approach was used for the nano-manufacturing of these amorphous catalysts. This nano-manufacturing route allowed the synthesis of fully amorphous nano-wires at room temperature for alloys with little or no noble-metal content. A wide range of nano-wires with varying aspect ratios from 25 to 120 was synthesized using commercially obtained anodic aluminum oxide (AAO) nano-molds. Cyclic voltammetry and chrono-amperometry demonstrated superior performance in terms of electrocatalytic activity and stability of the metallic glass nano-wires towards electro-oxidation of methanol. The mechanism for amorphization during pulsed electrodeposition is discussed and compared with the conventional approach of rapid quenching of the liquid melt. Amorphous alloys Catalyst Metallic Glass Electrodeposition Nano-manufacturing Fuel Cells Engineering, Materials Science Engineering, Metallurgy
3	Nano-Micro Materials Enabled Thermoelectricity From Window Glasses Inayat, Salman Bin 03 November 2012 (has links) With growing world population and decreasing fossil fuel reserves we need to explore and utilize variety of renewable and clean energy sources to meet the imminent challenge of energy crisis. Solar energy is considered as the leading promising alternate energy source with the pertinent challenge of off sunshine period and uneven worldwide distribution of usable sun light. Although thermoelectricity is considered as a reasonable energy harvester from wasted heat, its mass scale usage is yet to be developed. By transforming window glasses into generators of thermoelectricity, this doctoral work explores engineering aspects of using the temperature gradient between the hot outdoor heated by the sun and the relatively cold indoor of a building for mass scale energy generation. In order to utilize the two counter temperature environments simultaneously, variety of techniques, including: a) insertion of basic metals like copper and nickel wire, b) sputtering of thermoelectric films on side walls of individual glass strips to form the thickness depth of the glass on subsequent curing of the strips, and c) embedding nano-manufactured thermoelectric pillars, have been implemented for innovative integration of thermoelectric materials into window glasses. The practical demonstration of thermoelectric windows has been validated using a finite element model to predict the behavior of thermoelectric window under variety of varying conditions. MEMS based characterization platform has been fabricated for thermoelectric characterization of thin films employing van der Pauw and four probe modules. Enhancement of thermoelectric properties of the nano- manufactured pillars due to nano-structuring, achieved through mechanical alloying of micro-sized thermoelectric powders, has been explored. Modulation of thermoelectric properties of the nano-structured thermoelectric pillars by addition of sulfur to nano-powder matrix has also been investigated in detail. Using the best possible p and n type thermoelectric materials, this novel energy generation technique promises 304 watts of thermoelectricity from a 9 m2 glass window utilizing temperature difference of 20 OC. In addition to be useful even during off sunshine hours of the day, these energy harvesting windows will be capable of power generation even in the absence of a cooling systems inside the building as long as a natural temperature gradient exists between the two counter environments. With an increasing trend of having the exterior of buildings and high rises entirely made up of glass, this work offers an innovative transformation of these building exteriors into mass scale energy harvesters capable of running average lighting loads inside the building hence providing a complimentary source of electricity to the main power grid. Renewable Energy Thermoelectric Windows Green Building Technologies Nano-Manufacturing Mechanical Alloying
4	ULTRAFAST NANOSCALE PATTERNING SYSTEM: SURFING SCANNING PROBE LITHOGRAPHY Bojing Yao (12456495) 25 April 2022 (has links) <p> </p> <p>The development of the semiconductor industry is encountering a giant leap recently as Moorse’s is extended to the next levels. Advanced nanomanufacturing technology is the major challenge in the way. Higher resolution down to a few nanometers as well as higher throughput is always the key. As the optical lithography determines the feature size, the photomask is still in need of a low-cost and high resolution maskless patterning tool. In another aspect, the growing information allows the generation and storage of data at ever faster rates, which has led to the era of big data reaching a heroic amount of 7 zettabytes of total data in 2020. Future growth requires the total shipment of data storage capacity to double roughly every two years or less. For the future generation of magnetic data storage, the bit patterned medium (BPM) in combination with the current heat assisted magnetic recording (HAMR) is expected to increase the areal storage capacity by another order of magnitude by physically isolating magnetic bits at the nanoscale. Electron beam lithography (EBL) as a universal maskless lithography technique shows great resolution but has a high tool cost and low process throughput. Scanning probe lithography (SPL) is another family of nanoscale patterning techniques with low tool cost but the practical throughput is still limited. For example, dip pen nanolithography utilizes an AFM probe as a writing pen in direct patterning, but the ink delivery is limited by the rate of ink’s capillary transport. Other SPLs such as thermal probes with capabilities of 3D fabrication and surface oxidation via chemical reactions are all facing similar limitations in throughput. One way of breaking this limitation is to use parallel writing with millions of probes which also faces uniformity problems. </p> <p>In this Ph.D. dissertation, we report our Surfing Scanning Probe lithography (SSPL) method which can boost the scanning speed of SPL by several orders of magnitudes at a low cost by using a hydro-aero-dynamic scanning scheme. We use a homemade patterning head to continuously scan over a partially-wet spinning substrate at a linear speed of meters per second. The head carries several metallic tips which emit electrons and induce electrochemical reactions inside a gap of 10 nm scale. We use a liquid phase precursor and deliver it using the near-field electrospinning method and microfluid structures during the fast patterning. The best linewidth demonstrated is about 15 nm in full-width half maximum (FWHM) which can be further improved using smaller scanning gaps and sharp probe tips. Besides direct writing with a liquid precursor, SSPL can work with gas precursors as well enabled by nano plasma. The rate of material deposition is much high than conventional SPL. The SSPL system is a low-cost nanopatterning technology to produce patterns at high throughput and high resolution.</p> Mechanical Engineering Nanomanufacturing high-throughput nanolithography fast scanning probe air bearing surface hybrid flow electrohydrodynamic nanoplasma nanoscale patterning field emission nano manufacturing nano fabrication
5	One-photon 3D Nanolithography using Controlled Initiator Depletion Shih-hsin Hsu (13171584) 28 July 2024 (has links) <p> </p> <p>3D printing techniques have been applied in many fields to provide a potential for complex fabrication, and photopolymerization methods are the current possible path to fabricate nanoscale 3D structures. Multi-photon lithography is the most common tool to reach below 100-nm resolution. These methods require femtosecond lasers to reliably create sophisticated 3D polymeric nanostructures using nonlinear photopolymerization of a light-sensitive resin. Though these methods provide high accuracy and flexibility in advanced fabrication, they are essentially limited by their cost and throughput. Therefore, in this work, multiple approaches were examined to develop new methods for one-photon nonlinear 3D printing. </p> <p>By controlling multiple competing processes in the radical polymerization scheme, a nonlinear photopolymerization effect is achieved using a one-photon absorption process with the assistance of inhibition radicals and controlled diffusion. This work makes use of this nonlinear response to fabricate 2D/3D structures using a continuous-wave diode laser, demonstrating a significantly more cost-efficient source for 3D nanolithography. In addition, a numerical model was constructed with the highly nonlinear response by actively controlling the consumption of the initiators with the assistance of these inhibitors, and it shows the same trend of nonlinearity from experiments. We use this model to study this dosage-based nonlinear response driven by the laser intensity in several 1D and 2D scenarios with different inputs and predicted the polymerization results in a confined voxel in the resin to support the observations from the experiments. Besides the demonstration of current one-photon nonlinear 3D printing, this work also involves some results of nonlinear response by operating local oxygen concentration and a two-step absorption nonlinear photoinitiator. These results help us to further study the potential of increasing the throughput of the one-photon nonlinear 3D printing process. </p> <p>In conclusion, a new one-photon-based dose nonlinear process is introduced in this dissertation to achieve nanoscale 3D printing with a low-cost-405-nm diode laser operating at milliwatt level. By controlling the activation and transport of initiating and inhibiting radicals, we achieve patterning of the nanoscale features at a high scanning speed.</p> Microelectromechanical systems (MEMS) 3D printing Additive manufacturing Direct Laser Lithography one-photon polymerization nanoscale 3D-printing nano manufacturing Mechanical Engineering photopolymerization
6	Nanolithography on thin films using heated atomic force microscope cantilevers Saxena, Shubham 01 November 2006 (has links) Nanotechnology is expected to play a major role in many technology areas including electronics, materials, and defense. One of the most popular tools for nanoscale surface analysis is the atomic force microscope (AFM). AFM can be used for surface manipulation along with surface imaging. The primary motivation for this research is to demonstrate AFM-based lithography on thin films using cantilevers with integrated heaters. These thermal cantilevers can control the temperature at the end of the tip, and hence they can be used for local in-situ thermal analysis. This research directly addresses applications like nanoscale electrical circuit fabrication/repair and thermal analysis of thin-films. In this study, an investigation was performed on two thin-film materials. One of them is co-polycarbonate, a variant of a polymer named polycarbonate, and the other is an energetic material called pentaerythritol tetranitrate (PETN). Experimental methods involved in the lithography process are discussed, and the results of lithographic experiments performed on co-polycarbonate and PETN are reported. Effects of dominant parameters during lithography experiments like time, temperature, and force are investigated. Results of simulation of the interface temperature between thermal cantilever tip and thin film surface, at the beginning of the lithography process, are also reported. Characterization Deflection Setpoint Grain rearrangement Array Precise positioning Metrology Explosion Explosives Data storage Material Image processing Slow scan disabled Temperature Tip Local In-situ Nanoscale Electrical circuit fabrication Repair Co-polycarbonate Polymers Polycarbonates Energetic materials PETN Simulation Interface Nano-manufacturing Experiment Calibration Raman Frequency Deflagration Decomposition Detonation Build up Pile-up End capped End capping Cross linked Cross-linked Conductivity Microscale MEMS Microcantilever NEMS DPN tDPN Silicon Glass Peak InVOLS Manipulation AFM Atomic force microscope Defense Nanoscale Surface Stiffness Force Scan size Thermal cantilevers Imaging Lithography Nanolithography Thin films Cantilevers Heaters Technology Nanotechnology Scan velocity Scan rate Bake Anneal Pentaerythritol tetranitrate Thin films Thermal properties Atomic force microscopy Microlithography Nanotechnology Surfaces (Technology) Analysis

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