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Ab Initio and Density Functional Investigation of the Conformer Manifold of Melatonin and a Proposal for a Simple Dft-based Diagnostic for Nondynamical Correlation

Description: In this work we address two problems in computational chemistry relevant to biomolecular modeling. In the first project, we consider the conformer space of melatonin as a a representative example of “real-life” flexible biomolecules. Geometries for all 52 unique conformers are optimized using spin-component scaled MP2, and then relative energies are obtained at the CCSD (T) level near the complete basis set limit. These are then used to validate a variety of DFT methods with and without empirical dispersion corrections, as well as some lower-level ab initio methods. Basis set convergence is found to be relatively slow due to internal C-H…O and C-H…N contacts. Absent dispersion corrections, many DFT functionals will transpose the two lowest conformers. Dispersion corrections resolve the problem for most functionals. Double hybrids yield particularly good performance, as does MP2.5. In the second project, we propose a simple DFT-based diagnostic for nondynamical correlation effects. Aλ= (1-TAE [ΧλC]/TAE[XC])/λ where TAE is the total atomization energy, XC the “pure” DFT exchange-correlation functional, and ΧλC the corresponding hybrid with 100λ% HF-type exchange. The diagnostic is a good predictor for sensitivity of energetics to the level of theory, unlike most of the wavefunction-based diagnostics. For GGA functionals, Aλ values approaching unity indicate severe non-dynamical correlation. The diagnostic is only weakly sensitive to the basis set (beyond polarized double zeta) and can be applied to problems beyond practical reach of wavefunction ab-initio methods required for other diagnostics.
Date: August 2013
Creator: Fogueri, Uma

The Academic Steroid: Nonmedical Use of Prescription Stimulants at a North Texas University

Description: The goal of this study was to determine the extent, motivations, and justifications of nonmedical prescription stimulant use among the population at a large public university in the North Texas region. Participants consisted of 526 undergraduate students enrolled at the studied university during the spring and summer 2014 semesters. The findings of the study suggest that the nonmedical use by students was higher than the findings in much of the current literature, but was within the parameters established in the literature. The primary motivation for nonmedical use was academic in nature and was justified by moderation of nonmedical use to strategic academic times.
Date: December 2014
Creator: Pennington, Cody W.

Accelerated Corrosion Test with Operation Simulation of All-Aluminum Microchannel Heat Exchangers

Description: The HVAC&R industry is looking to transition from copper-aluminum heat exchangers to all-aluminum microchannel technology. The want for the transition stemmed from seeing the performance improvement of all-aluminum microchannel radiators in the automotive industry. Applications differ between the two industries; therefore, applying this technology for HVAC&R use must be validated. Research towards operating modes of an all-aluminum heat exchanger in a defined corrosive environment will provide the industry with a better understanding of heat exchanger design and heat exchanger material selection. The worth in this is preventing overdesign and producing more efficient heat exchangers. Furthermore, ASHRAE members and the corrosion community will find value in a defined corrosion system and corrosion test procedure. The information gained through past research has progressed assessment of material performance; however, the methods improperly simulate and expedite natural weathering. The most common method being used is the ASTM (American Society of Testing Materials) Sea Water Acetic Acid Test. The research discussed in this paper was focused on improving a standard corrosion system by implementing system modifications to simulate heat exchanger operation while performing a modified wet-dry cyclic test (e.g. ASTM G85 Annex 5). The goal is to produce results that are more representative of natural corrosion behavior and its forms. Current results were gathered from five of ten samples that underwent initial testing. Finally, possible improvements towards the chamber system and the test method, including the salt solution, are discussed.
Date: May 2016
Creator: Vaughan, Haydn

The Acceptance and Use of Cloud Computing Services by Small and Medium Enterprises in Lagos, Nigeria

Description: This study explored the acceptance of cloud computing (CC) services by small and medium enterprises (SMEs) in Lagos, Nigeria, which has been missing from CC services literature. It aimed to understand the motivations for adoption, the uses of the services, and the benefits they derive from it. The uses and gratification theory was applied as the theoretic framework for this endeavor. An online survey with close-ended and open-ended questions was distributed to 1200 randomly selected participants through email. In total, 392 valid responses were collected and analyzed using descriptive statistics and categories. The results found that SMEs in Lagos, Nigeria had a low level of awareness and appreciation of CC services. The adoption rate was also low. Unlike their counterparts in other regions, SMEs primary concerns were service downtime, stable power supply, and better internet access. The study found that SMEs were not taking full advantage of the capabilities of CC services. Some sections, however, were doing better than others, such as the information and communications sub-sector. This study suggested that targeted interventions should be conducted to raise the awareness of CC services in SMEs, and to improve their efficient and effective use of CC services. The uses and gratification theory was appropriate for guiding this study to understand the acceptance and use of CC services by SMEs in Lagos, Nigeria.
Date: May 2017
Creator: Azogu, Olajumoke O

Accidental Activists: Mark Phariss, Vic Holmes, and Their Fight for Marriage Equality in Texas

Description: In early 2013 same-sex marriage was legal in only ten states and the District of Columbia. That year the Supreme Court’s decision in United States v. Windsor appeared to open the door to marriage equality. In Texas, Mark Phariss and Vic Holmes, together for sixteen years and deeply in love, wondered why no one had stepped across the threshold to challenge their state’s 2005 constitutional amendment prohibiting same-sex marriage. They agreed to join a lawsuit being put together by Akin Gump Strauss Hauer & Feld LLD. Two years later—after tense battles in the Federal District Court for the Western District of Texas and in the Fifth Circuit Court of Appeals, after sitting through oral arguments at the Supreme Court of the United States in Obergefell v. Hodges—they won the right to marry deep in the heart of Texas. But the road they traveled was never easy. Accidental Activists is the deeply moving story of two men who struggled to achieve the dignity of which Justice Anthony Kennedy spoke in a series of Supreme Court decisions that recognized the “personhood,” the essential humanity of gays and lesbians. Author David Collins tells Mark and Vic’s story in the context of legal and social history and explains the complex legal issues and developments surrounding same-sex marriage in layman’s terms.
Date: August 2017
Creator: Collins, David

ActivAmerica

Description: Drawing from fairy tales, ghost stories, and science-fiction, the stories in ActivAmerica explore how we confront (and exert) power and re-imagine ourselves through sports and athletic activities. A group of girls starts an illicit hockey league in a conservative suburb. A recently separated woman must run a mile a day in order to maintain her new corporate health insurance. Children impacted by environmental disaster create a “mutant soccer team.” Two sisters are visited by an Olympic gymnast who demands increasingly dangerous moves from them. Sports allow the characters to form communities on soccer fields and hidden lakes, in overgrown backyards and across Ping-Pong tables. Throughout the collection, however, athletic risk also comes with unexpected, often unsettling results.
Date: November 2017
Creator: Cass, Meagan

Acute Effects of the Antibiotic Streptomycin on Neural Network Activity and Pharmacological Responses

Description: The purpose of this study is to find out that if antibiotic streptomycin decreases neuronal network activity or affects the pharmacological responses. The experiments in this study were conducted via MEA (multi-electrode array) technology which records neuronal activity from devices that have multiple small electrodes, serve as neural interfaces connecting neurons to electronic circuitry. The result of this study shows that streptomycin lowered the spike production of neuronal network, and also, sensitization was seen when neuronal network pre-exposed to streptomycin.
Date: December 2014
Creator: Zeng, Wei Rong

Adhesion and Surface Energy Profiles of Large-area Atomic Layers of Two-dimensional MoS2 on Rigid Substrates by Facile Methods

Description: Two-dimensional (2D) transition metal dichalcogenides (TMDs) show great potential for the future electronics, optoelectronics and energy applications. But, the studies unveiling their interactions with the host substrates are sparse and limits their practical use for real device applications. We report the facile nano-scratch method to determine the adhesion energy of the wafer scale MoS2 atomic layers attached to the SiO2/Si and sapphire substrates. The practical adhesion energy of monolayer MoS2 on the SiO2/Si substrate is 7.78 J/m2. The practical adhesion energy was found to be an increasing function of the MoS2 thickness. Unlike SiO2/Si substrates, MoS2 films grown on the sapphire possess higher bonding energy, which is attributed to the defect-free growth and less number of grain boundaries, as well as less stress and strain stored at the interface owing to the similarity of Thermal Expansion Coefficient (TEC) between MoS2 films and sapphire substrate. Furthermore, we calculated the surface free energy of 2D MoS2 by the facile contact angle measurements and Neumann model fitting. A surface free energy ~85.3 mJ/m2 in few layers thick MoS2 manifests the hydrophilic nature of 2D MoS2. The high surface energy of MoS2 helps explain the good bonding strength at MoS2/substrate interface. This simple adhesion energy and surface energy measurement methodology could further apply to other TMDs for their widespread use.
Date: May 2016
Creator: Wu, Min

The Aesthetics of Sin: Beauty and Depravity in Early Modern English Literature

Description: This dissertation argues that early modern writers such as William Shakespeare, Thomas Middleton, George Herbert, John Milton, and Andrew Marvell played a critical role in the transition from the Neoplatonic philosophy of beauty to Enlightenment aesthetics. I demonstrate how the Protestant Reformation, with its special emphasis on the depravity of human nature, prompted writers to critique models of aesthetic judgment and experience that depended on high faith in human goodness and rationality. These writers in turn used their literary works to popularize skepticism about the human mind's ability to perceive and appreciate beauty accurately. In doing so, early modern writers helped create an intellectual culture in which aesthetics would emerge as a distinct branch of philosophy.
Date: December 2017
Creator: Jeffrey, Anthony Cole

Age Friendly Cities: The Bureaucratic Responsiveness Effects on Age Friendly Policy Adoption

Description: Challenging a long-held attachment to the medical model, this research develops a cultural model placing local governments at the center of policy making and refocusing policy attention on mobility, housing, the built environment and services. To examine the phenomenon of age friendly policy adoption by cities and the magnitude of adoption, a 21-question web-based survey was administered to a sample of 1,050 cities from the U.S. Census having a population over 10,000 and having at least 14% of their population aged 65 years and over. The goal of the questionnaire was to help identify what kind of policy objectives cities establish to facilitate the opportunity for older adults to live healthy and independent lives in their communities as they age. Multiple linear and ordinal regression models examined the likelihood of policy action by cities and provide evidence as to why some cities support more age friendly policy actions than others. Evidence illustrates theoretical advancement providing support for a cultural model of aging. The cultural model includes multiple factors including bureaucratic responsiveness reflected in the management values of the administration. Findings show variation in the integration of a cultural awareness of aging in the municipality's needs assessment, strategic goals, citizen engagement strategies, and budgetary principles. Cities with a cultural awareness of aging are more likely to adopt age friendly policies. Findings also provide support for the argument that the public administrator is not the driving sole factor in decision making. A shared spaced with mobilized citizen need of individuals 65 and over is identified.
Date: May 2017
Creator: Keyes, Laura Marie

All Over the Map: True Heroes of Texas Music

Description: A lavishly illustrated collection of forty-two profiles of Texas music pioneers, most underrated or overlooked, All Over the Map: True Heroes of Texas Music covers the musical landscape of a most musical state. The first edition was published in 2005 to wide acclaim. This second edition includes updated information, a bonus section of six behind-the-scenes heroes, and fifteen new portraits of Lefty Frizzell, Janis Joplin, and others, spanning such diverse styles as blues, country, hip-hop, conjunto, gospel, rock, and jazz. D.J. Stout and Pentagram designed the reborn edition, with photographer Scott Newton providing portraits. Michael Corcoran has been writing about Texas music for more than thirty years, for the Dallas Morning News and Austin American Statesman, as well as in such publications as Texas Monthly and Spin. These pieces are based on his personal interviews with their subjects as well as in-depth research. Expertly written with flair, the book is a musical waltz across Texas. A Lone Star state of mind -- East Texas -- Soul Stirrers (Trinity). In search of Rebert Harris -- Harry Choates (Port Arthur). Death in a jail cell -- Barbara Lynn (Beaumont). The empress of Gulf Coast soul -- Janis Joplin (Port Arthur). Lust for love -- Clarence "Gatemouth" Brown (Orange). Count Basie of the blues -- Houston -- Geto Boys and D.J. Screw. Where the dirty South began -- Floyd Tillman. Honky tonk triple threat -- Milt Larkin Orchestra. Birth of the Texas tenors -- Archie Bell and the Drells with the Tsu Toronados. "Hey, everybody, that's me!" -- Dallas/ Fort Worth area -- Ray Price (Mount Pleasant). "The good times, my ass!" -- T-Bone Walker (Oak Cliff). Architect of electric blues -- Townes Van Zandt (Fort Worth). Poet -- Ella Mae Morse (Mansfield). "You sing like a black girl." -- King Curtis (Fort ...
Date: May 2017
Creator: Corcoran, Michael

American Blitzkrieg: Courtney Hodges and the Advance Toward Aachen (August 1 - September 12, 1944)

Description: This is an analysis of combat operations of US First Army under the command of Courtney Hodges, between August 1 and September 12, 1944, with an emphasis upon 1st, 4th, 9th, and 30th Divisions. However, other formations are necessarily discussed in order to maintain context. Indeed, many historians have failed to emphasize the complex interdependent nature of these efforts, and the traditional narrative has been distorted by inadequate situational awareness. This study argues that the army's operations were exceedingly difficult, resulting in approximately 40,000 casualties over a six week period. Although historians claim that the Germans were essentially defeated by the end of July, and that the Allied advance was subsequently halted by logistical difficulties, the official combat records clarify that logistical shortages were a tertiary factor, as the enemy remained capable of strong resistance. Consequently, defensive efforts were the primary factor hindering the advance, in conjunction with deteriorating weather conditions, rugged terrain, and surprisingly severe traffic congestion. Although this was mobile warfare, military theorists have overestimated the effectiveness of mechanization and underestimated the potential for antitank defenses. Ultimately, this study asserts that First Army was the primary American combat formation, and historians have exaggerated the importance of George Patton's Third Army. Therefore, in order to understand an American way of war, the combat operations of First Army deserve far more attention than they have previously received. This narrative thus emphasizes forgotten battles, including: Tessy, St. Sever, Tete, Perriers, Mayenne, Ranes, Flers, Mace, Elbeuf, Mantes, Corbeil, Sevran, Mons, Cambrai, Philippeville, Dinant, and Aubel.
Date: December 2012
Creator: Rinkleff, Adam J.

American Indian Worldviews, Risk Perceptions and Disaster Planning: an Exploratory Study

Description: It is commonly assumed that when confronted with an imminent hazard that people will react rationally, and prepare for, or at least attempt to avoid, danger from pending disasters. However, this conventional wisdom is not as evident as it appears. People prepare for, react to, or take social action to avoid hazards when they perceive the risk of danger to be threatening enough to warrant action, providing one has the will, insight and resources to do so. However, not all people perceive risks similarly. Risk is perceived differently by different people which affects risk perception and responses to hazards. This dissertation explores the relationships between American Indian worldviews, risk perceptions and disaster planning. To carry out this research 28 American Indians were interviewed. The sample consists of 14 American Indians residing in a rural are on the northern plains and 14 urban American Indians. The results only partially support that worldview is linked to risk perception and subsequent disaster planning. Other factors found to relate to risk perception and disaster planning for this non-representative sample of American Indians include various forms of social vulnerability.
Date: December 2013
Creator: Bales, Rodney A.

Americans Who Would Not Wait: The American Legion of the Canadian Expeditionary Force, 1915-1917

Description: This dissertation examines the five battalions of the Canadian Expeditionary Force designated as the American Legion. Authorized in Canada between 1915 and 1917, these units were formed to recruit volunteers from the United States to serve in the Canadian Overseas Contingent during the First World War. This work reviews the organization of Canada’s militia and the history of Anglo-American relations before examining the Canadian war effort, the formation of the American Legion, the background of its men, and the diplomatic, political, and constitutional questions that it raised. Much of the research focuses on the internal documents of its individual battalions (the 97th, 211th, 212th, 213th and 237th) and the papers of Reverend Charles Bullock now housed at the Public Archives of Canada. Documentation for the diplomatic furor the American Legion caused comes largely through the published diplomatic documents, British Foreign Office records held at the Public Record Office at Kew, and United States Department of State files at the National Archives at College Park, Maryland. The most useful sources for American Legion correspondence are the Beaverbrook papers held at the House of Lords Record Office, the papers of Canadian Prime Minister Sir Robert Laird Borden, and those of the Governor-General, the Duke of Connaught found in the Public Archives of Canada. During its brief existence the American Legion precipitated diplomatic and political problems in the United States, the United Kingdom, and the Dominion of Canada. Among the issues raised by the controversy surrounding the American Legion were: the relationship between the dominion government in Canada and the British government; the structural problems of imperial communications; the rise of a Canadian national identity and the desire for greater autonomy; and, the nature of citizenship and expatriation. This dissertation is also a long overdue account of the thousands of United States citizens ...
Date: August 2012
Creator: Smylie, Eric Paul

Analysis and Optimization of Graphene FET based Nanoelectronic Integrated Circuits

Description: Like cell to the human body, transistors are the basic building blocks of any electronics circuits. Silicon has been the industries obvious choice for making transistors. Transistors with large size occupy large chip area, consume lots of power and the number of functionalities will be limited due to area constraints. Thus to make the devices smaller, smarter and faster, the transistors are aggressively scaled down in each generation. Moore's law states that the transistors count in any electronic circuits doubles every 18 months. Following this Moore's law, the transistor has already been scaled down to 14 nm. However there are limitations to how much further these transistors can be scaled down. Particularly below 10 nm, these silicon based transistors hit the fundamental limits like loss of gate control, high leakage and various other short channel effects. Thus it is not possible to favor the silicon transistors for future electronics applications. As a result, the research has shifted to new device concepts and device materials alternative to silicon. Carbon is the next abundant element found in the Earth and one of such carbon based nanomaterial is graphene. Graphene when extracted from Graphite, the same material used as the lid in pencil, have a tremendous potential to take future electronics devices to new heights in terms of size, cost and efficiency. Thus after its first experimental discovery of graphene in 2004, graphene has been the leading research area for both academics as well as industries. This dissertation is focused on the analysis and optimization of graphene based circuits for future electronics. The first part of this dissertation considers graphene based transistors for analog/radio frequency (RF) circuits. In this section, a dual gate Graphene Field Effect Transistor (GFET) is considered to build the case study circuits like voltage controlled oscillator (VCO) and low ...
Date: May 2016
Creator: Joshi, Shital

Analysis and Performance of a Cyber-Human System and Protocols for Geographically Separated Collaborators

Description: This dissertation provides an innovative mechanism to collaborate two geographically separated people on a physical task and a novel method to measure Complexity Index (CI) and calculate Minimal Complexity Index (MCI) of a collaboration protocol. The protocol is represented as a structure, and the information content of it is measured in bits to understand the complex nature of the protocol. Using the complexity metrics, one can analyze the performance of a collaborative system and a collaboration protocol. Security and privacy of the consumers are vital while seeking remote help; this dissertation also provides a novel authorization framework for dynamic access control of resources on an input-constrained appliance used for completing the physical task. Using the innovative Collaborative Appliance for REmote-help (CARE) and with the support of a remotely located expert, fifty-nine subjects with minimal or no prior mechanical knowledge are able to elevate a car for replacing a tire in an average time of six minutes and 53 seconds and with an average protocol complexity of 171.6 bits. Moreover, thirty subjects with minimal or no prior plumbing knowledge are able to change the cartridge of a faucet in an average time of ten minutes and with an average protocol complexity of 250.6 bits. Our experiments and results show that one can use the developed mechanism and methods for expanding the protocols for a variety of home, vehicle, and appliance repairs and installations.
Date: December 2017
Creator: Jonnada, Srikanth

Angular Analysis of a Wide-Band Energy Harvester based on Mutually Perpendicular Vibrating Piezoelectric Beams

Description: The recent advancements in electronics and the advents of small scaled instruments has increased the attachment of life and functionality of devices to electrical power sources but at the same time granted the engineers and companies the ability to use smaller sources of power and batteries. Therefore, many scientists have tried to come up with new solutions for a power alternatives. Piezoelectric is a promising material which can readily produce continuous electric power from mechanical inputs. However, their power output is dependent upon several factors such as, system natural frequency, their position in the system, the direction of vibration and many other internal and external factors. In this research the working bandwidth of the system is increased through utilizing of two different piezoelectric beam in different directions. The dependency of output power with respect to rotation angle and also the frequency shift due to the rotation angle is studied.
Date: December 2016
Creator: Mirzaabedini, Sohrab

“The Angular Degrees of Freedom” and Other Stories

Description: The preface, " Performing Brain Surgery: The Problematic Nature of Endings in Short Fiction," deals with the many and varied difficulties short story writers encounter when attempting to craft endings. Beginning with Raymond Carver and Flannery O’Connor and moving to my own work, I discuss some of the obscure criteria used to designate a successful ending, as well as the more concrete idea of the ending as a unifying element. Five short stories make up the remainder of this thesis: "In-between Girls," "Crocodile Man," "Surprising Things, Sometimes Amusing," "Good Jewelry," and "The Angular Degrees of Freedom."
Date: December 2014
Creator: Feagin, Aprell McQueeney

Aphorismen, Capriccio, and Heptameron for Piano Solo By Jürg Baur: a Performer's Guide

Description: The purpose of this dissertation is to give instruction regarding the performance of three important piano works by Jürg Baur (1918-2010). Aphorismen, Capriccio, and Heptameron stand out as his most significant piano works both because of their length and because of their pianistic complexity. Since Baur had a successful career as both teacher and composer during his lifetime, his acclaimed works received many honors in Germany. His works can be performed by intermediate to advanced students. Intermediate students can easily offer simpler pieces like Aphorismen in competitions, while pieces like Capriccio and Heptameron better are suited to a more advanced level. Although some of his compositions are difficult to perform compared with other modern German works, Baur's music is more accessible. In the article, "Auf der Spuren der alten Zeit" Baur is quoted to state that Paul Hindemith and Bela Bartok's music influenced his own compositional ideas. However, although Baur is a modern composer, he didn't write in a totally atonal style, but rather attempted to broaden tonality. While Heptameron is atonal, Aphorismen and Capriccio give the impression of tonality, thus they are more accessible to the audience. I was fortunate enough to study Aphorismen with Baur as well as receiving advice for performance of Capriccio and some movements of Heptameron. Therefore, I gained a primary source of instruction, particularly in regards to pedal markings, rhythmic indications, voice balancing, finger suggestions, articulation markings, and tone of musical expression. In this dissertation, I include my own instructions (accepted by the composer) along with the composer's intentions.
Date: December 2012
Creator: Park, Esther

Application of Cyclic Polarization of Aluminum 3003 Used in All-Aluminum Microchannel Heat Exchangers

Description: All-aluminum microchannel heat exchangers are designed to significantly reduce refrigerant charge requirements, weight, reduced brazed joints, and decreased potential for leakage by increasing reliability. Al 3003 alloy is corrosion resistant and can be formed, welded, and brazed but the issue with all-aluminum heat exchangers is localized corrosion (pitting) in corrosive environments. Currently, there is no universally accepted corrosion test that all coil manufacturers use to characterize their products. Electrochemical testing method of cyclic polarization was employed in this investigation and relevant parameters including electrolyte corrosive agent and its concentration, electrolyte pH, and applied potential scan rate was varied to find an optimal set of parameters. Results of cyclic polarization of Al 3003 in electrolytes containing various concentrations of NaCl were compared with those of the tests in Sea Water Acidified Accelerated Test (SWAAT) electrolyte and it is shown the SWAAT electrolyte (4.2% sea salt acidified to pH of 2.9) is by far stronger (in terms of corrosivity) than typical 3.5% NaCl solution used in most corrosion testing. Corrosion rates (g/m2yr) of Al 3003 measured in this investigation were comparable to those provided by ISO 9223 standard corresponding to C1 through CX categories. Duration of cyclic polarization test is much shorter than that of SWAAT and results obtained in this test is more reproducible compared to those of SWAAT. Scanning electron microscopy micrographs show typical pit depths of about 50 μm.
Date: May 2015
Creator: Barnes, Javier

Application of UV-Vis Spectroscopy to the Monitoring, Characterization and Analysis of Chemical Equilibria of Copper Etching Baths

Description: The continuously increasing demand for innovation in the miniaturization of microelectronics has driven the need for ever more precise fabrication strategies for device packaging, especially for printed circuit boards (PCBs). Subtractive copper etching is a fundamental step in the fabrication process, requiring very precise control of etch rate and etch factor. Changes in the etching chemical equilibrium have significant effects on etching behavior, and CuCl2 / HCl etching baths are typically monitored with several parameters including oxidation-reduction potential, conductivity, and specific gravity. However, the etch rate and etch factor can be difficult to control even under strict engineering controls of those monitoring parameters. The mechanism of acidic cupric chloride etching, regeneration and recovery is complex, and the current monitoring strategies can have difficulty controlling the interlocking chemical equilibria. A complimentary tool, thin-film UV-Vis spectroscopy, can be utilized to improve the current monitoring strategies, as UV-Vis is capable of identifying and predicting etching behavior that the current standard methodologies have difficulty predicting. Furthermore, as a chemically-sensitive probe, UV-Vis can investigate the complex changes to the chemical equilibrium and speciation of the etch bath, and can contribute overall to significant improvements in the control of the copper etching system in order to meet the demands of next-level design strategies.
Date: August 2017
Creator: Lambert, Alexander S