Nanotechnology Fabrication Commons^™

Investigating Nano-Coated Surfaces In Improvement Wear Resistance Of Tillage Tools, Saeed Mehrang Marani, Gholamhossein Shahgholi, Saeed Kanoon Marani

Emirates Journal for Engineering Research

The blade in the tillage operation has the most interaction with soil particles. It causes the wear and tear of this piece and reduces its expected life span. Tillage tool wear is of great importance to farmers in terms of economic aspects, reduced quality tillage operations, and increased power consumption. The aim of this study is to investigate wearing of five materials including st37 steel (SST37) plate, galvanized steel (GAS), and fiberglass (GFRP), and two coatings (i.e., titanium nano-nitride (nano-TiN) and tantalum carbide (nano-TaC)) by sputtering in the plasma medium of the layer based on conventional steel. These pieces were …

Influence Of Flow Rate, Nozzle Speed, Pitch And The Number Of Passes On The Thickness Of S1805 Photoresist In Suss Microtec As8 Spray Coater, Rohan Sanghvi, Gyuseok Kim

Tool Data

S1805 positive photoresist has been deposited on single crystalline Si wafers using a Suss MicroTec Alta Spray. The influence of flow rate, nozzle speed, pitch and number of passes on the thickness of the photoresist was studied. Results show that the thickness of S1805 is linearly proportional to the flow rate and number of passes, and inversely proportional to the nozzle speed and pitch.

Correction Of Pattern Size Deviations In The Fabrication Of Photomasks Made With A Laser Direct-Writer, Ningzhi Xie, George Patrick Watson

Protocols and Reports

When using Heidelberg DWL66+ laser writer to fabricate the photomask, the pattern feature dimensions may have deviations. These deviations can be caused by the lithography process and the undercut in the metal etch process. The same deviation value of 0.8µm was found to appear in all the patterns independent of the pattern original size and local pattern density. To overcome this universal deviation, a universal bias is suggested to be applied to the original patterns during the data preparation for the lithography process. In order to ensure this pre-exposure bias method can work, both the laser direct-write exposure conditions (laser …

Influence Of Naoh Concentration On Transfer Process Of Graphene, Francisco Saldana, Chengyu Wen, George Patrick Watson

Protocols and Reports

The process of transferring a monolayer of graphene using two different concentrations of sodium hydroxide (NaOH) solution unto a silicon dioxide (SiO2) coated Si chip using electrochemistry was performed. The transfer process is crucial for the delamination of a continuous graphene monolayer film from copper foil. After examining and inspecting the integrity of the graphene monolayer, it was observed that the lower concentration to NaOH led to slower rate of hydrogen bubble generation; this condition was found to be less destructive and yielded a graphene film with fewer visible tears.

Investigation Of The Electrode Polarization Effect For Biosensor Applications, Anil Koklu

Mechanical Engineering Research Theses and Dissertations

My research focuses on electrokinetic transport. Particularly, in this dissertation, we focus on fabrication and testing of micro electrodes with nanostructured surfaces to minimize the electrode polarization (EP) effects for biosensor applications. In the first study, electrochemical deposition of gold nanoparticles on to planar gold electrodes was used to generate rough surfaces. Dendritic nanostructures that reduced EP up to two orders of magnitude was obtained by optimizing the deposition conditions. These structures also enhanced dielectrophoresis (DEP) response of our bio-chips, making them usable in physiological buffers. In further studies we discovered a universal scaling of EP in the frequency domain, …

Smart Charging Of Future Electric Vehicles Using Roadway Infrastructure, Sara Ahmed, Ethan Ahn, Mahmoud Reda Taha, Samer Dessouky, Moneeb Genedy, Daniel Fernandez, Ann Sebestian, Patience Raby

Data

Corresponding data set for Tran-SET Project No. 18ITSTSA03. Abstract of the final report is stated below for reference:

"Inspired by the fact that there is an immense amount of renewable energy sources available on the roadways such as mechanical pressure and frictional heat, this study presented the development and implementation of an innovative charging technique for future electric vehicles (EVs) by fully utilizing the existing roadways and the state-of-the-art nanotechnology and power electronics. The project introduced a novel wireless charging system, SIC (Smart Illuminative Charging), that uses LEDs powered by piezoelectric nanomaterials as the energy transmitter source and thin film …

Toolpath Planning Methodology For Multi-Gantry Fused Filament Fabrication 3d Printing, Hieu Trung Bui

Graduate Theses and Dissertations

Additive manufacturing (AM) has revolutionized the way industries manufacture and prototype products. Fused filament fabrication (FFF) is one of the most popular processes in AM as it is inexpensive, requires low maintenance, and has high material utilization. However, the biggest drawback that prevents FFF printing from being widely implemented in large-scale production is the cycle time. The most practical approach is to allow multiple collaborating printheads to work simultaneously on different parts of the same object. However, little research has been introduced to support the aforementioned approach. Hence a new toolpath planning methodology is proposed in this paper. The objectives …

Pixelated Gasb Membranes For Photovoltaics: Fabrication And Structure-Property Relationships, Vijay Saradhi Mangu

Electrical and Computer Engineering ETDs

In this thesis, I present a reliable and efficient approach to heterogeneous integration of single-crystalline GaSb semiconductors with highly mismatched materials. The mismatch may refer to the crystalline structure and the thermal expansion coefficient of single-crystalline GaSb and the other materials of interest. The strategy of hetero-integration relies on epitaxial lift-off. This approach prevents the formation of extended structural defects that are detrimental to the performance of optoelectronic devices and preserves GaSb growth substrates for potential reuse.

Within my research work, I have overcome some outstanding challenges of epitaxial lift-off of GaSb, and I have demonstrated the operation of single-crystalline …

Towards Stable Electrochemical Sensing For Wearable Wound Monitoring, Sohini Roychoudhury

FIU Electronic Theses and Dissertations

Wearable biosensing has the tremendous advantage of providing point-of-care diagnosis and convenient therapy. In this research, methods to stabilize the electrochemical sensing response from detection of target biomolecules, Uric Acid (UA) and Xanthine, closely linked to wound healing, have been investigated. Different kinds of materials have been explored to address such detection from a wearable, healing platform. Electrochemical sensing modalities have been implemented in the detection of purine metabolites, UA and Xanthine, in the physiologically relevant ranges of the respective biomarkers. A correlation can be drawn between the concentrations of these bio-analytes and wound severity, thus offering probable quantitative insights …

Silica-Coated Metallic Nanoparticle-Based Hierarchical Super-Hydrophobic Surfaces Fabricated By Spin-Coating And Inverse Nanotransfer Printing, Shengjie Zhai, Hui Zhao

Mechanical Engineering Faculty Publications

By combining spin coating and inverse nanotransfer printing, silica-coated gold nanoparticles are patterned onto polydimethylsiloxane (PDMS) superhydrophobic surfaces to form a hierarchical structure. A layer of nanoparticles is spin-coated on a flat silicon substrate serving as the stamp, which is then transferred to the raised regions of PDMS surfaces. Our inverse nanotransfer printing is in contrast to the standard nanotransfer printing, which transfers metal from the raised regions of a stamp to a flat PDMS surface. The fabricated hierarchical surface exhibits a higher contact angle and delays the Cassie-Wenzel transition during evaporation of a sessile droplet, indicating an improvement of …

Structural Health Monitoring Of Composite Parts: A Review, Jacob Pessin

Honors Theses

Structural health monitoring has the potential to allow composite structures to be more reliable and safer, then by using more traditional damage assessment techniques. Structural health monitoring (SHM) utilizes individual sensor units that are placed throughout the load bearing sections of a structure and gather data that is used for stress analysis and damage detection. Statistical time based algorithms are used to analyze collected data and determine both damage size and probable location from within the structure. While traditional calculations and life span analysis can be done for structures made of isotropic materials such as steel or other metals, composites …

Symmetry And Dopant Diffusion In Inverted Nanopyramid Arrays For Thin Crystalline Silicon Solar Cells, Seok Jun Han

Chemical and Biological Engineering ETDs

In this dissertation, we enhance the efficiency of thin flexible monocrystalline silicon solar cells by breaking symmetry in light trapping nanostructures and improving homogeneity in dopant concentration profile. These thin cells are potentially less expensive than conventional thick silicon cells by using less silicon material and making the cells more convenient to be handled when supported on polymer films. Moreover, these cells are widely applicable due to their flexibility and lightweight. However, for high efficiencies, these cells require effective light trapping and charge collection. We achieve these in cells based on 14-mm-thick free-standing silicon films with light-trapping arrays of nanopyramidal …

Characterization Of Hydride Vapor Phase Epitaxy Grown Gan Substrates For Future Iii-Nitride Growth, Alaa Ahmad Kawagy

Graduate Theses and Dissertations

The aim of this research is to investigate and characterize the quality of commercially obtained gallium nitride (GaN) on sapphire substrates that have been grown using hydride vapor phase epitaxy (HVPE). GaN substrates are the best choice for optoelectronic applications because of their physical and electrical properties. Even though HVPE GaN substrates are available at low-cost and create the opportunities for growth and production, these substrates suffer from large macro-scale defects on the surface of the substrate.

In this research, four GaN on sapphire substrates were investigated in order to characterize the surface defects and, subsequently, understand their influence on …

Plasmonic Properties Of Nanoparticle And Two Dimensional Material Integrated Structure, Desalegn Tadesse Debu

Graduate Theses and Dissertations

Recently, various groups have demonstrated nano-scale engineering of nanostructures for optical to infrared wavelength plasmonic applications. Most fabrication technique processes, especially those using noble metals, requires an adhesion layer. Previously proposed theoretical work to support experimental measurement often neglect the effect of the adhesion layers. The first finding of this work focuses on the impact of the adhesion layer on nanoparticle plasmonic properties. Gold nanodisks with a titanium adhesion layer are investigated by calculating the scattering, absorption, and extinction cross-section with numerical simulations using a finite difference time domain (FDTD) method. I demonstrate that a gold nanodisk with an adhesive …

Reactive Ion Etching Selectivity Of Si/Sio2: Comparing Of Two Fluorocarbon Gases Chf3 And Cf4, Meiyue Zhang, Pat Watson

Protocols and Reports

Two reactive ion etching (RIE) processes were studied to show the relative etch selectivity between SiO2 and Si using two fluorocarbon gases, CF4 and CHF3. Results show that CHF3 gives better selectivity (16:1) over CF4 (1.2 :1). On the other hand, the etch rate of SiO2 of CF4 is approximately 52.8 nm/min, faster than CHF3 (32.4 nm/min).

Fabrication And Characterization Of Nanofiber Nylon-6-Mwcnt As An Electrochemical Sensor For Sodium Ions Concentration Detection In Sweat, Kelsey Mills

Williams Honors College, Honors Research Projects

Fabrication and characterization nylon-6-MWCNT nanofiber as an electrochemical sensor to detect sodium ion concentrations specifically in sweat. Using contact angle to determine surface morphology and chronoamperometry testing to identify ideal sensor conditions, tests optimized parameters like weight percent of nylon or other polymers, carbon nanotube (CNT) isomer, and solution concentration to determine reproducibility of functional sensors. Utilizing the electric qualities of carbon nanotubes partnered with the sodium ion selectivity of calixarene treatment and polymers unique properties like flexibility and scalability create open an arena for optimizing sodium ion sensors for further development for functional prototypes. Morphology tests showed that the …

Straintronic Nanomagnetic Devices For Non-Boolean Computing, Md Ahsanul Abeed

Theses and Dissertations

Nanomagnetic devices have been projected as an alternative to transistor-based switching devices due to their non-volatility and potentially superior energy-efficiency. The energy efficiency is enhanced by the use of straintronics which involves the application of a voltage to a piezoelectric layer to generate a strain which is ultimately transferred to an elastically coupled magnetostrictive nanomaget, causing magnetization rotation. The low energy dissipation and non-volatility characteristics make straintronic nanomagnets very attractive for both Boolean and non-Boolean computing applications. There was relatively little research on straintronic switching in devices built with real nanomagnets that invariably have defects and imperfections, or their adaptation …

Energy Efficient Spintronic Device For Neuromorphic Computation, Md Ali Azam

Theses and Dissertations

Future computing will require significant development in new computing device paradigms. This is motivated by CMOS devices reaching their technological limits, the need for non-Von Neumann architectures as well as the energy constraints of wearable technologies and embedded processors. The first device proposal, an energy-efficient voltage-controlled domain wall device for implementing an artificial neuron and synapse is analyzed using micromagnetic modeling. By controlling the domain wall motion utilizing spin transfer or spin orbit torques in association with voltage generated strain control of perpendicular magnetic anisotropy in the presence of Dzyaloshinskii-Moriya interaction (DMI), different positions of the domain wall are realized …

Fabrication And Characterization Of Planar-Structure Perovskite Solar Cells, Guoduan Liu

Theses and Dissertations--Electrical and Computer Engineering

Currently organic-inorganic hybrid perovskite solar cells (PSCs) is one kind of promising photovoltaic technology due to low production cost, easy fabrication method and high power conversion efficiency.

Charge transport layers are found to be critical for device performance and stability. A traditional electron transport layer (ETL), such as TiO₂ (Titanium dioxide), is not very efficient for charge extraction at the interface. Compared with TiO₂, SnO₂ (Tin (IV) Oxide) possesses several advantages such as higher mobility and better energy level alignment. In addition, PSCs with planar structure can be processed at lower temperature compared to PSCs with …

Tuning The Reactivity Of Nanoenergetic Gas Generators Based On Bismuth And Iodine Oxidizers, Mkhitar A. Hobosyan, Karen S. Martirosyan

Physics and Astronomy Faculty Publications and Presentations

There is a growing interest on novel energetic materials called Nanoenergetic Gas- Generators (NGGs) which are potential alternatives to traditional energetic materials including pyrotechnics, propellants, primers and solid rocket fuels. NGGs are formulations that utilize metal powders as a fuel and oxides or hydroxides as oxidizers that can rapidly release large amount of heat and gaseous products to generate shock waves. The heat and pressure discharge, impact sensitivity, long term stability and other critical properties depend on the particle size and shape, as well as assembling procedure and intermixing degree between the components. The extremely high energy density and the …