Tradition begins with innovation. The rich and complicated history of Printmaking is shaped by invention and discovery. I see this advancement for the sole purpose to distribute knowledge and ideas to every person regardless of prosperity and status. At its core intention is the need to make art and knowledge accessible. The procedural research I have been exploring along side my artist research was designed to do just as invention in printmaking has done before. I have applied my knowledge and availability of modern technology with traditional ways print artists create. These new processes are geared to make photomechanical practices in lithography and intaglio cheaper and more accessible to artists and students with limited resources. I have also included a statement about the artwork that has been able to be developed because of this research to provide context for my artistic practice.

Visible light emitting diodes (LEDs) are widely used in daily consumer electronics systems, such as general lighting, displays, communication, sensing, and also biomedical applications. To mitigate the ever increasing technology demand, there are tremendous on-going efforts in improving material properties and micro-fabrication techniques. In general, visible LEDs are environmentally friendly, robust and reliable light emitters with small device footprint, and are capable of delivering high luminous efficacy. Typically, LEDs rely on group-III-nitride materials to generate visible light. One of the techniques to generate white light is to coat blue LEDs with yellow phosphor, or ultraviolet (UV) LEDs with red-green-blue (RGB) phosphor. Other scheme relies on combination of RGB LEDs, where high brightness green and blue LEDs are generally grown on robust sapphire substrate. But the current challenges in high threading dislocation density of III-Nitride materials on sapphire or hetero-substrate, phosphor degradation, and bulk-LED mechanical design constraints imposed by the supporting substrate wafer motivate further scientific investigations into strain-engineering, novel reliable phosphor-semiconductor, color-tuning techniques, and transferrable III-nitride vertical LEDs. The current research presents a significant step towards the utilization of annealed porous GaN as a template for subsequent growth of fully relaxed GaN-based epitaxy materials. In our study, we observed significant compressive strain relaxation of 0.41 ± 0.04 GPa in annealed porous GaN fabricated using UV-assisted electroless etching. Moreover the use of GaN nanoparticles with large wavelength tunability and 10 µm InGaN microstructures with different indium composition ushers a new way of making reliable phosphor for white light generation. We also investigate the epitaxial lift-off of InGaN LED structures by selectively etching unintentionally doped GaN sacrificial buffer layer. High GaN/InGaN etching selectivity of 100/1 and with GaN lateral etch-rate of 5 µm/min was achieved using the photo assisted electroless etching process. The kinetics of electron hole transfer in the diffusion limited etching reaction is discussed. Transferred LEDs onto flexible and glass substrates showed ~10 times higher optical power output, 2 times lower series resistance and a lower turn-on voltage than bulk LEDs fabricated from the same wafer. This innovative technique offers a low cost optoelectronic platform for the formation of pixelated red, green and blue (RGB) display on any flexible, transparent or rigid substrates. The technique will also enable new platform for sensing, wearable electronics/optoelectronics and biomedical applications.

"My understanding of the purpose of this paper is the criticism and evaluation of the candidate's exhibition, as partial fulfillment of the requirements for the Master of Arts degree. I interpret this program as it applies not only to the paintings collectively and individually, but as it affects the observer. An evaluation of the paintings as a group will involve a critical discussion of their individual merits and their place in the process of development, as well as a clarification of purpose to help explain their existence. This clarification, to be amplified later, must necessarily touch on the area dealing with values which give life import for me, since art is a way of living and growing, and the paintings are a record of it"--Chapter 1. / "February, 1952." / Typescript. / "Submitted to the Graduate Council of Florida State University in partial fulfillment of the requirements for the degree of Master of Arts." / Advisor: Edmund D. Lewandowski, Major Professor. / Includes bibliographical references (leaf 39).

Indiana University-Purdue University Indianapolis (IUPUI) / An investigation was conducted into the effect of acid etching of the enamel and the use of pins on the retention of direct filling resins when used for restoration of fractured incisor teeth. The retention secured by these techniques as related to the cavity design also was studied. Four different cavity preparations were used. The retention of the resin in all four was compared when there was no pretreatment of the enamel, when the enamel was etched by 50 per cent phosphoric acid, and when pins were used for retention. Retention was assessed on the basis of resistance of the restoration to displacement by a lingual force. No significant difference was observed in retention as related to cavity design in the control specimens. In all four cavity preparations, acid etching of the enamel and the use of two retentive pins increased the resistance of the restorations to displacement. (However; when only one "L" shaped retentive pin was employed in Conjunction with a flat incisal preparation the force required to accomplish displacement was no greater than for controls.) The acid etch technique when employed with a cavity preparation that extended 1.7 mm. or more onto the lingual surface of the enamel generally offered a higher resistance to lingual force than double pin retained restorations. There was no significant difference between the resistance offered by a circumferential preparation when the resin was retained by either acid etching or by two pins. In the acid etch technique the enamel surface area and its distribution are important factors in retention.

OBJECTIVES: This in-vitro study aimed to evaluate the effect of hydrofluoric acid etching and airborne particle abrasion on zirconia bond strength, using three different types of cement. To assess the impact of hydrofluoric acid etching on zirconia surface roughness and investigate the effect of hydrofluoric acid etching on zirconia's surface topography, microstructure, and crystal structure. MATERIALS AND METHODS: Crown-abutment simulation systems were constructed, using a custom-made zirconia tapered ring model and tapered titanium pin-abutments. Twelve groups were included in the study and classified according to the surface treatment and type of cement used. Each group had 10 specimens for a total of 120 test specimens. The fully sintered zirconia ring was alumina particle abrasion (APA) treated with a 50-μm alumina and/or etched with 9.5% HF acid, solution for 1 minute. The Ti pin was APA treated with 125-μm alumina. Three different types of cement were used: one RMGIC (GC FujiCem Evolve) and two resin composite types of cement (Panavia SA Universal and Panavia V5). A cementing jig was used to standardize the cementation process of the titanium pins to the zirconia rings. An Instron was used to obtain the retention load values. The failure load between the zirconia ring and the titanium pin was determined using an axial pullout test and the values were statistically analyzed for the effects of etching treatment, APA treatment, and cement type using JMP Pro 16. Zirconia-disk specimens were constructed using a custom-made disk model. Thirteen groups were included in the study and classified according to the hydrofluoric acid etching concentrations, consistencies, and timing used. Each group had 3 specimens. The total specimen size was thirty-nine specimens. Disks were polished and etched using 5% HF, 9.5% HF, and 40% HF acid etching concentrations, gel, and solution consistencies, and for 1 and 15 minutes of etching time. Disks were examined with an SEM, X-Ray diffractometer, and a profilometer for microstructure, crystallography, and surface roughness, respectively. RESULTS: HF acid-etching treatment significantly increased retention load compared to non-etched groups. There was no significant difference in retention load between APA-treated and non-APA-treated groups. Groups cemented with Panavia V5 showed a higher retention load compared to GC FujiCem Evolve and Panavia SA Universal. There was no significant difference in the surface roughness among the etched groups and the control groups. Roughening of the crystal boundaries with irregularities and pits was observed under SEM. As etching time and concentration increased the surface became rougher and more irregular. There were no obvious crystal structure differences between the etched groups and non-etched groups. CONCLUSIONS: Significantly different retention loads were found among tested groups. Hydrofluoric acid etching increases the bond strength of zirconia and titanium, using resin composite cement. Using hydrofluoric acid etching to pre-treat the zirconia surface may be an alternative approach to obtain sufficient bonding strength.

Gallium oxide (Ga2O3) has been the subject of extensive research activity due to its ultrawide bandgap and large breakdown field, which make it promising for next-generation applications in deep ultraviolet detection and power electronics. β-Ga2O3 is the most thermally stable and well-studied polymorph of Ga2O3. However, during the past decade, the metastable orthorhombic κ-Ga2O3 has emerged as an equally impressive candidate material owing to its high crystal symmetry and ferroelectric and spontaneous polarization properties. Several studies have reported the growth and characterization of κ-Ga2O3 films using different epitaxial growth methods. However, the existing literature still lacks reports on the processing of this material for future device applications. Therefore, in this thesis, we investigate the effects of high-temperature treatment and plasma exposure on the structural and optical properties of mist chemical vapor deposition (mist-CVD)-grown κ-Ga2O3 films. Using high-temperature X-ray diffraction (HT-XRD), we show that the films remain phase-pure up to an annealing temperature of 800 ˚C, after which β-phase peaks start to appear and eventually show a complete transition to β-Ga2O3 at 875 ˚C. Additionally, we show using detailed high-resolution transmission electron microscopy (HRTEM) and XRD analyses that annealing at 700 ˚C in ambient air is effective in improving the crystal quality of the κ-Ga2O3 layer by relieving in-plane strains and epitaxial stacking faults. Moreover, since dry etching is needed for the anisotropic patterning of materials for device applications, it is necessary to investigate the effects of plasma exposure on the near-surface properties of the material in order to keep its damage to a minimum. Therefore, we studied the impacts of plasma exposure during dry etching on the chemical structure, crystallinity, and optical properties of κ-Ga2O3 by using a variety of characterization methods. We observed how varying the etching parameters using BCl3/Ar can affect the near-surface properties of the material, which play a key role in modifying the performance of future devices. Specifically, we found that both RIE/ICP power and BCl3/Ar ratio can influence the surface stoichiometry and the concentration of native defect density, which affect the material’s structural and optical properties. Additionally, we reported for the first time on κ-Ga2O3 ICP-RIE process optimization using a BCl3/Ar gas mixture. By tuning the process parameters, the optimized recipe had a high etch rate of 130 nm/min, showed a surface roughness reduction of 56%, and produced vertical sidewall profiles for ridge device structures.

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