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Characterization Of Processes Used In Nanofabrication Of Digital Electrostatic E-Beam Array Lithography (Deal) Devices, Ryan Benjamine Rucker

Masters Theses

The ultimate goal of this research was to nanofabricate an advanced field emission electron beam lithography platform using an electron beam induced deposition process (EBID) to deposit tungsten (W) nanofibers cathodes. In order to fabricate the devices, it was necessary to characterize the reactive ion etching (RIE) processes for the fabrication of the Digital Electrostatic e-beam Array Lithography (DEAL) device. To optimize the reactive ion etch processes of the silicon and silicon dioxide layers, a JMP desktop statistical discovery software from SAS® was employed to design a set of experiments. The design of experiments (DOE) employed variable conditions of R.F. …

On The Measurement Of Yield Strength By Spherical Indentation, Erik G. Herbert

Masters Theses

Over the past 10 years, a number of investigators have proposed methods to measure the yield strength of metals using instrumented indentation experiments performed with a sphere [1-6]. Among the proposed methods that are easy to implement experimentally and do not require any additional novel characterization techniques or proprietary software analysis are those of Field and Swain, Yu and Blanchard, Ma et al., Cao and Lu, Kogut and Komvopoulos, and Lee, Lee, and Pharr. However, these methods have yet to be rigorously verified experimentally. The objectives of this work are twofold: first, identify the basic principles, predictions, data analysis routine, …

Influence Of Material Variables In Thermal Bonding Of Nonwovens, Raghavendra Ratnakar Hegde

Masters Theses

The goal of this research was to understand the bonding behavior of different polymers in thermal bonding. Special attention was given to the interaction of the materials variables with processing characteristics of the polymers.

Initially, thermal bonding studies were done using films from different polymers. Polymer films of different morphology were produced from different grades of polypropylene. Thermal bonding of these films was carried out using the hot press. Effect of film structure, properties and bonding conditions on the bonding efficiency was studied. A range of bond temperatures covering poor, optimum and over bond- ing were studied to understand the …

The Study Of Overload Effects On Fatigue-Crack-Growth Behavior By Neutron Diffraction, Yinan Sun

Masters Theses

During the load-controlled high-cycle fatigue test, when the overload was applied, it is shown that from the crack-growth rate (da/dN) versus stress-intensity-factor range (∆K) curve, the crack-growth rate decreased, following the overload, which indicates the crack-closure phenomenon. The crack-growth-retardation period was observed after the overload. The goal of this study is to investigate the deformation evolution during tensile loading and unloading cycles using neutron diffraction.

Neutron diffraction is used to investigate the crack-closure phenomenon by measuring the changes in the elastic-lattice-strain profiles around the fatigue-crack tip in a compact-tension (CT) specimen during tensile loading and unloading cycles. Spatially-resolved-strain measurements were …

Direct Microstructure Deposition By Micromirror Direct Patterning And Laser Sintering Of Nanoparticles, Weiya Fang

Masters Theses

"The emerging demand for low cost, medium volume production and flexible micro-fabrication techniques has been advanced by the development of MEMS and limitations of the existing technique. As a promising building block for future MEMS and IC industry, nanoparticles are attracting more and more attention due to their interesting electronic, catalytic and optical properties, which can be finely tuned by varying their size. A novel process for the manufacturing of functional microstructures by modulated laser direct patterning and curing of nanoparticles is presented.

The first part of the thesis aims to understand the possibility and process of using modulated laser …