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open access

The Effect of a Free-Time Contingency on Arithmetic and Problem Behavior in the Classroom

Description: This investigation is concerned with demonstrating the effects of an easily managed classroom contingency-management treatment package on increasing arithmetic performance while decreasing disruptive behavior for whole classes of students. The study proposed, among other things, that programs differ in the degree to which each student must depend upon other students for reinforcement
Date: August 1976
Creator: Ross, James M.
Partner: UNT Libraries
open access

Igor Stravinsky's Use of the Bassoon in his Compositions from 1908 to 1948

Description: Igor Stravinsky is widely considered one of the most important and influential composers of the 20th century and a pivotal figure in modernist music. This study analyzed how Stravinsky absorbed the bassoon's solo and ensemble functions which he inherited and later significantly extended the scope of these functions by adapting them to his individual needs. The study concluded that Stravinsky's compositions are and will remain important landmarks in the history of bassoon literature.
Date: August 1973
Creator: Schroeder, Daniel F.
Partner: UNT Libraries
open access

Trauma, Posttraumatic Stress Disorder Symptoms, and COVID-19 Impacts among South Asians

Description: South Asians are the third fastest growing racial/ethnic minority group in the United States with distinct cultural characteristics. The coronavirus disease 2019 (COVID-19) pandemic has disproportionately impacted racial and ethnic minorities in the U.S, including South Asians, across several life domains: work, home life/education, social activities, economic, emotional and physical health, infection, quarantine, and positive changes. The COVID-19 pandemic may have critically impacted South Asians with traumatic event experiences and posttraumatic stress disorder (PTSD) symptom severity across several life domains. Limited work suggests high rates of interpersonal traumas and substantial PTSD symptom severity in the South Asian community. Uniquely, the current study examined which life domains impacted by the COVID-19 pandemic associated with a greater count of traumatic event types, interpersonal vs. non-interpersonal traumas, and PTSD symptom severity. Results revealed that negative experiences in social activities, as well as distress in economic, emotional, and physical health domains, were significantly associated with the count of traumatic event types. Negative social activity experiences, and distress in the economic and emotional health domains, were also significantly associated with PTSD symptom severity. Quarantine and physical health domains significantly associated with the count of interpersonal traumas, while COVID-19-related experiences (in social, quarantine, and infection domains) significantly associated with the count of non-interpersonal traumas. Findings inform clinically relevant pandemic research in a vulnerable population and provide trauma and PTSD prevalence estimates in the South Asian community.
Date: August 2022
Creator: Rafiuddin, Hanan S.
Partner: UNT Libraries
open access

Scaling, Power-Law First Return Times, and Non-Ergodicity

Description: This dissertation is a collection of papers on anomalous phenomena in physics, biology, and sociology. These phenomena are primarily analyzed in terms of their temporal and spatiotemporal statistical properties. The analysis is based on both numerical simulations and, in some cases, real-world physiological and sociological data. The primary methods of analysis are diffusion entropy analysis, power spectral analysis, multifractal analysis, and survival (or waiting-time) analysis.
Date: August 2022
Creator: Lambert, David Robert
Partner: UNT Libraries

Optimizing Value Co-Creation in Education Supply Chains: An Evaluation of Determinants and Resiliency in Service Systems

Description: Services and service-based business are a major part of any economy. However, service-based supply chains require a greater level of interaction between provider and consumer than the traditional manufacturing or product-based supply chain. Therefore, they require optimization and resiliency models that acknowledge the constraints and goals unique to service-based industries. Value co-creation and service-dominant logistics (SDL) are relatively new to operations research. Existing literature in management science provides a framework for value co-creation but does not provide a model for optimizing value cocreation and resiliency in a complex or dynamic systems such as education supply chains (ESC). This dissertation addresses these knowledge gaps through 3 essays. The first essay establishes a method for optimizing investment in resiliency measures when utilizing parallel supply chains. The essay examines the intersection of value co-creation theory between higher education and service-dominant logistics (SDL) to understand the role of supply chain elements in value cocreation. The second essay provides a theoretical approach to incorporating resilience planning into the customer relationship management model. The final essay establishes a method for optimizing investment in resiliency measures when utilizing parallel service supply chains.
This item is restricted from view until September 1, 2027.
Date: August 2022
Creator: Smith, Justin Thomas
Partner: UNT Libraries

Adjustments in Business Operations during the COVID-19 Pandemic: An Analysis of Natural and Cultural Resource Sites in Texas

Description: This research expands the theoretical concept of human adjustment to floods established by Gilbert F. White and incorporates his adjustment concept to examine the range of adjustments in business operations adopted by Texas' natural and/or cultural resources sites during the first year of the COVID-19 pandemic. This mixed-methods study consisted of an online survey with a follow-up semi-structured phone interview. The survey data was analyzed using descriptive statistics and the interview data was inductively coded for thematic analysis as well as quantitative and qualitative content analyses. Specifically, this study identifies the adjustment measures undertaken by these entities to maintain business operations while reducing the virus spread; analyses the direct and indirect factors influencing adjustment measures; examines new business opportunities that emerged from these adjustments; and evaluates whether the impact of COVID-19 on these entities varied in terms of entity characteristics. Findings indicate that cultural and/or natural resource sites implemented adjustments to maintain their fiscal stability and/or to protect human health; these serve as direct underlying motivating factors for these entities. To support these direct measures, indirect factors influenced the operations thus required adjustments such as staffing, volunteers, technology, funding, and donations. Additionally, new opportunities in business practices emerged while implementing these adjustments such as networking, maintenance, and virtual options. Across all entity types, virtual programs was a key adjustment addressing both fiscal and health concerns. From these adjustments, this study provides recommendations for cultural and/or natural resource sites to implement to improve resilience to future extreme events.
This item is restricted from view until September 1, 2023.
Date: August 2022
Creator: Tamima, Salvesila
Partner: UNT Libraries
open access

Investigating the Role of Concurrent Verbal Behavior in a Rule-Shifting Scenario

Description: The present study evaluates the effects of incompatible verbal behavior when engaging in the Wisconsin Card Sorting Test (WCST). The WCST is a complex task that requires participants to match stimulus cards based on self-generated rules. After a varying number of trials, the rule changes and the participant will have to self-generate a new rule. Verbal behavior, specifically joint control, is likely involved in rule-following. Seven participants took part in this study. Participants engaged in the WCST either silently or while performing a putatively incompatible behavior, counting backward from 100 to 0. Results suggest joint control might be involved as when participants engaged in the incompatible behavior their performance was affected in terms of lower accuracy and longer reaction times compared to the silent baseline.
Date: August 2022
Creator: Cutler, Jacquelyn Marie
Partner: UNT Libraries
open access

On the Descriptive Complexity and Ramsey Measure of Sets of Oracles Separating Common Complexity Classes

Description: As soon as Bennett and Gill first demonstrated that, relative to a randomly chosen oracle, P is not equal to NP with probability 1, the random oracle hypothesis began piquing the interest of mathematicians and computer scientists. This was quickly disproven in several ways, most famously in 1992 with the result that IP equals PSPACE, in spite of the classes being shown unequal with probability 1. Here, we propose what could be considered strengthening of the random oracle hypothesis, using a stricter notion of what it means for a set to be 'large'. In particular, we suggest using largeness with respect to the Ramsey forcing notion. In this new context, we demonstrate that the set of oracles separating NP and coNP is 'not small', and obtain similar results for the separation of PSPACE from PH along with the separation of NP from BQP. In a related set of results, we demonstrate that these classes are all of the same descriptive complexity. Finally we demonstrate that this strengthening of the hypothesis turns it into a sufficient condition for unrelativized relationships, at least in the three cases considered here.
Date: August 2022
Creator: Creiner, Alex
Partner: UNT Libraries

Factors Influencing Continued Usage of Telemedicine Applications

Description: This study addresses the antecedents of individuals' disposition to use telemedicine applications, as well as the antecedents of their usage to provide insight into creating sustained usage over time. The theoretical framework of this research is Bhattacherjee's expectation-confirmation IS continuance model. By combining a series of key factors which may influence the initial and continued usage of telemedicine applications with key constructs of Bhattacherjee's IS continuance model, this study aims to provide a deeper understanding of barriers to telemedicine app usage and how to facilitate continued use of these apps. Online survey data was collected from college students who are telemedicine application users. A total of 313 responses were gathered, and data analysis was conducted using SmartPLS 3. This dissertation contributes by looking at the IS adoption and IS continuance research simultaneously to connect these two research streams as well as suggesting the usage context of some established IS theory being different with regard to healthcare applications.
This item is restricted from view until September 1, 2024.
Date: August 2022
Creator: Liu, Xiaoyan
Partner: UNT Libraries

The Informational Effects of Non-Deal Roadshows

Description: Non-deal roadshows (NDR) are privately held one-on-one meetings between the buy-side of financial institutions and firm management. Using a novel dataset of these meetings, I examine the effects that NDR meetings have on the outcomes of two important corporate events: seasoned equity offerings (SEOs) and mergers and acquisitions (M&As). I also study the potential implications of the information content in NDRs on the behavior of stock returns following earnings announcements, which has been the subject of much academic work. I structure the dissertation in three essays. In the first essay, I examine the relationship between NDR activity and the underpricing of SEOs. I find that NDRs are associated with lower SEO underpricing. This association is stronger for firms with infrequent NDR activity, for smaller firms, and for firms with higher analysts' forecast errors. These findings suggest that NDRs reduce the level of asymmetric information between firms and investors, which results in a lower cost of raising equity. In Essay 2, I investigate whether the occurrence of NDR meetings affects post-earnings-announcement drift (PEAD). I find that PEAD declines after NDR activity when the most recent NDR meeting occurs within one month before the earnings announcement. This decline is most pronounced among smaller firms, firms with high idiosyncratic volatility, and firms with Friday earnings announcements. These findings suggest that NDRs are mechanisms to convey earnings-specific information about forthcoming earnings. In the third essay I explore the relationship between NDRs, the medium of exchange used in M&As and the value created by this important corporate event. I show that NDR activity is important to understand the cross-sectional variation of the excess returns around M&As, and the bid premium. NDRs are also relevant to understand the medium of exchange. This relevance of NDR is more pronounced when the firms involved have higher levels of …
This item is restricted from view until September 1, 2023.
Date: August 2022
Creator: Howell, Dylan A.
Partner: UNT Libraries
open access

The Emergence of All-State Vocal Jazz Ensembles in the United States from 1978 to 2022

Description: Since the creation of the first all-state vocal jazz ensemble in 1978, similar ensembles have been established in roughly half of the United States. This paper contains historical summaries of the creation of all-state vocal jazz ensembles in nineteen of those states, primarily as recounted via interviews with those ensembles' founders. Each semi-structured interview was conducted over video conference or phone and lasted approximately one hour; resulting interview data was analyzed using qualitative methods. During the creation of each ensemble the respective founders needed to secure the support of a host organization, determine where and when to convene, and decide how to address auditions, sound reinforcement, rhythm sections, and funding. The diversity of solutions to these shared challenges reflects the diverse priorities of each founder as well as the unique conditions in which each all-state vocal jazz ensemble was established. However, several elements were common across these stories, including the influence of existing festivals and all-state ensembles, and tensions within the choral education community regarding the value of the vocal jazz idiom relative to traditional choirs, show choirs, and other vocal ensembles. In a few cases, established all-state vocal jazz ensembles were discontinued; these stories further illustrate the challenges such ensembles face and the conditions that foster their perpetuation.
Date: August 2022
Creator: Thomas, Tyler
Partner: UNT Libraries

Processing-Structure-Property Correlation for Additively Manufactured Metastable High Entropy Alloy

Description: In the present study both fusion based - laser powder bed fusion (LPBF), and solid state - additive friction stir deposition (AFSD) additive manufacturing processes were employed for the manufacturing of a metastable high entropy alloy (HEA), Fe40Mn20Co20Cr15Si5 (CS-HEA). A processing window was developed for the LPBF and AFSD processings of CS-HEA. In case of LPBF, formation of solidification related defects such as lack of fusion pores (for energy density ≤ 31.24 J/mm3) and keyhole pores (for energy density ≥ 75 J/mm3) were observed. Variation in processing conditions affected the microstructural evolution of the metastable CS-HEA; correlation between processing conditions and microstructure of the alloy is developed in the current study. The tendency to transform and twin near stress concentration sites provided excellent tensile and fatigue properties of the material despite the presence of defects in the material. Moreover, solid state nature of AFSD process avoids formation of solidification related defects. Defect free builds of CS-HEA using AFSD resulted in higher work hardening in the material. In summary, the multi-processing techniques used for CS-HEA in the present study showcase the capability of the AM process in tailoring the microstructure, i.e., grain size and phase fractions, both of which are extremely critical for the mechanical property enhancement of the alloy.
This item is restricted from view until September 1, 2023.
Date: August 2022
Creator: Agrawal, Priyanshi
Partner: UNT Libraries
open access

Earth Abundant Transition Metal Catalysts for Activation and Functionalization of Light Hydrocarbons

Description: Light hydrocarbons activations, functionalization, and reactions have been a subjects of catalysis research for decades but dominated by the rarer and more expensive noble metals. Switching over to using the more earth abundant third row transition metals could be more economical and less toxic but come with their own challenges. Their use as catalysts with light hydrocarbons could be employed better utilize and more efficiently use our hydrocarbon resources that the world still depends on.
Date: August 2022
Creator: Grumbles, William M
Partner: UNT Libraries

On the Utility of Surface Electromyography-Based Biofeedback on Rehabilitation from Total Knee Arthroplasty: A Clinical Trial

Description: Knee osteoarthritis affects approximately 25 million adults. In severe cases, total knee arthroplasty (TKA) is the most common solution. TKA is effective at addressing pain and reducing continued degeneration of articular cartilage. However, effective physical therapy (PT) following TKA is vital for a full functional recovery. Despite the importance of PT, half of patients never achieve a full functional recovery. Decreases in proprioceptive feedback, severe atrophy, and pain inhibition all likely contribute to the variability in effectiveness. Surface electromyography-based biofeedback (sEMGBF) may allow clinicians to address some of these barriers by supplementing proprioceptive feedback and targeting small muscle contractions before eventually increasing the contraction requirement. Using a between group design, we compare the effectiveness of sEMGBF (7) to neuromuscular stimulation (NMES) (6), and a control group (6) in recovery following TKA. Effectiveness was evaluated across 4 metrics (quadriceps strength, range of motion, functional improvement, and quality of life) in a pre-test/post-test fashion. At the statistical level this study suggest that sEMGBF leads to greater improvements in quadriceps strength relative to the NMES and control group. Additionally, visual analysis suggests that sEMGBF may also lead to greater improvements in range of motion, and functional improvement relative to the NMES and control group. The results for quality of life are mixed. Overall, the study provides initial clinical support for the utility of sEMGBF following TKA.
This item is restricted from view until September 1, 2027.
Date: August 2022
Creator: Armshaw, Brennan
Partner: UNT Libraries

Occupancy Monitoring Using Low Resolution Thermal Imaging Sensors

Description: Occupancy monitoring is an important research problem with a broad range of applications in security, surveillance, and resource management in smart building environments. As a result, it has immediate solutions to solving some of society's most pressing issues. For example, HVAC and lighting systems in the US consume approximately 45-50% of the total energy a building uses. Smart buildings can reduce wasted energy by incorporating networkable occupancy sensors to obtain real-time occupancy data for the facilities. Therefore, occupancy monitoring systems can enable significant cost savings and carbon reduction. In addition, workplaces have quickly adapted and implemented COVID-19 safety measures by preventing overcrowding using real-time information on people density. While there are many sensors, RGB cameras have proven to be the most accurate. However, cameras create privacy concerns. Hence, our research aims to design an efficient occupancy monitoring system with minimal privacy invasion. We conducted a systematic study on sensor characterization using various low-resolution infrared sensors and proposed a unified processing algorithms pipeline for occupancy estimation. This research also investigates low-resolution thermal imaging sensors with a chessboard reading pattern, focusing on algorithm design issues and proposing solutions when detecting moving objects. Our proposed approach achieves about 99% accuracy in occupancy estimation, enabling many practical smart building applications. We also added additional sensors to our system using sensor fusion technology to boost its functionality and demonstrated the system's feasibility by deploying it in different real-time application scenarios.
This item is restricted from view until March 1, 2023.
Date: August 2022
Creator: Chidurala, Veena
Partner: UNT Libraries
open access

Desertion and Defection in Roman Republican Warfare

Description: Despite their many successes, Roman leaders continually struggled with indiscipline in their own ranks as they battled Rome's opponents. Desertion and defection were steps that soldiers often undertook to avoid their obligated service. Previous scholarship has largely overlooked this aspect of Roman warfare. This dissertation analyzes why Roman soldiers began turning to desertion and defection throughout the Republican period. Such cases were generally rare in early Rome, but the expanding responsibilities and hardships of warfare in the Middle Republic caused them to rise, as did the sizeable growth of the Roman community. The civil wars of the Late Republic saw especially high cases of such acts, as generals incentivized defections in their opponents ranks. Roman desertion was not unique, but a common occurrence in ancient warfare. This dissertation also addresses how Romans capitalized on desertion and defection in warfare. The Second Punic War offers an example of how Rome achieved victory by encouraging defection in its enemy's alliances. Romans also relied heavily on defectors as a source of intelligence and as a tool in siege warfare. The moral forces of commitment, discipline, dissatisfaction, and desertion were often as important as the tactics and technologies of the participants in Rome's wars.
Date: August 2022
Creator: Stampher, Matthew Joseph
Partner: UNT Libraries

An Evaluation of Differential Attention on Preferred Topics of Conversation for Adults with Autism Spectrum Disorder

Description: Extensive speech on preferred conversation topics may limit conversations with others. For individuals with ASD, extensive speech on a topic may be a form of restricted or repetitive behavior that may be addressed through skill building. However, previous research suggests that skill building may not be necessary if the behavior is sensitive to differential reinforcement contingencies. To evaluate the effects of differential reinforcement in the form of attention on conversation topics, we replicated the results of Stocco et al. by assessing sensitivity to conversational attention with participant-only topic initiations. Additionally, we extended the procedures by evaluating the effects of topic initiations from the participant and the experimenter (shared initiations). Similar to previous research, our results yielded that speech was sensitive to conversational attention across all participants. That is, differential reinforcement contingencies altered levels of speech on topics of conversation, indicating that differential reinforcement procedures may be sufficient in addressing performance deficits. Lastly, we assessed participant preference for participant-only initiation or shared initiation conversations.
This item is restricted from view until September 1, 2023.
Date: August 2022
Creator: Castillo, Michelle Victoria
Partner: UNT Libraries

Microstructure Evolution and Mechanical Response of Material by Friction Stir Processing and Modeling

Description: In this study, we have investigated the relationship between the process-microstructure to predict and modify the material's properties. Understanding these relationships allows the identification and correction of processing deficiencies when the desired properties are not achieved, depending on the microstructure. Hence, the co-relation between process-microstructure-properties helped reduce the number of experiments, materials & tool costs and saved much time. In the case of high entropy alloys, friction stir welding (FSW) causes improved strength due to the formation of fine grain structure and phase transformation from f.c.c to h.c.p. The phase transformation is temperature sensitive and is studied with the help of differential scanning calorimetry (DSC) to calculate the enthalpy experimentally to obtain ΔGγ→ε. The second process discussed is heat treatment causing precipitation evolution. Fundamental investigations aided in understanding the influence of strengthening precipitates on mechanical properties due to the aging kinetics – solid solution and variable artificial aging temperature and time. Finally, in the third case, the effect of FSW parameters causes the thermal profile to be generated, which significantly influences the final microstructure and weld properties. Therefore, a computational model using COMSOL Multiphysics and TC-Prisma is developed to generate the thermal profile for different weld parameters to understand its effect on the microstructure, which would eventually affect and predict the final properties of the weld. The model's validation is done via DSC, TEM, and mechanical testing.
This item is restricted from view until September 1, 2023.
Date: August 2022
Creator: Gupta, Sanya
Partner: UNT Libraries

An Explanation of Racial Attitudes Utilizing Intergroup Threat Theory and Group Empathy Theory

Description: This project examined the effects of threat perceptions and group empathy on racial outgroup attitudes. The relationship between threat perception and increased racial prejudice has been well established within the literature, but the effect of group empathy within this dynamic has been largely undocumented. The following study utilizes data from the American National Election Study 2020 Time Series to analyze racial outgroup attitudes among subsamples of Blacks (n = 726), Hispanics (n = 762), and Whites (n = 5,962). Along with threat perception, group empathy was found to be a salient predictor of outgroup attitudes. These results suggest that an effective technique to reduce negative outgroup attitudes would aim to reduce perceptions of outgroups as threatening and increase group empathy.
This item is restricted from view until March 1, 2023.
Date: August 2022
Creator: Larrison, KayLynn Marie
Partner: UNT Libraries
open access

Digital Covens: An Ethnographic Examination of the Intersection of Paganism and Social Media

Description: This paper examines how does within the Pagan community uses social media, specifically Facebook groups, as a way of community building, knowledge gathering, and platform for digital ritual. The research was based on a combination of interviews and observational data gathered from various groups. To help analyze the data gathered, theoretical approaches of both mediatization and materiality are employed to understand how digital spaces are being used as a tool for those within the Pagan community within their religious tool-kit, as well as understanding how digital landscapes are being used in order to conduct ritual.
Date: August 2022
Creator: Ferguson, Carlise Pamela
Partner: UNT Libraries
open access

Community Perceptions of Wildfire Risk and Mitigation in Colorado Springs

Description: This research assessed wildfire mitigation and risk perceptions in two neighborhood in Colorado Springs, CO. Semi-structured interviews were used during transect walks with participants. The research compared residents' perspectives to fire personnel's knowledge.
Date: August 2022
Creator: Caruolo, Cara Danielle
Partner: UNT Libraries
open access

Mastery in Colonial and Post-Colonial Brazil: José Maurício Nunes Garcia's (1767-1830) Use of Trombone in His "Missa De Santa Cecília" (1826)

Description: Padre José Maurício Nunes Garcia (1767-1830) was perhaps the most prolific, revered, and successful composer in 18th and 19th century colonial and postcolonial Brazil. Padre José Maurício's favor with King Dom João VI, the Portuguese Royal Court, and a catalogue of hundreds of compositions, is validation of his success, yet there is comparatively little academic research and recognition in comparison to his European contemporaries. Padre José Maurício's employment of the trombone within his ambitious capstone, his Missa de Santa Cecília showcases his recognizable and original compositional language. The influence of two contemporaries of Padre José Maurício, Wolfgang Amadeus Mozart (1756-1791) and Gioachino Rossini (1792-1868), had an integral and clear influence on the Missa de Santa Cecília without resulting in rote imitation. Mozartian text emphasis, independent part writing, technical demand, and traditional use of the trombone for sacred or supernatural imagery were synthesized by Padre José Maurício swiftly and originally. Simultaneously, Rossinian orchestration, close scoring, limited range, subverted structural arrivals, and emulated percussive effects were personalized and employed by Padre José Maurício. His insular development and instantaneous adaptation of new orchestration and theatrical models yields trombone writing that is idiomatic, in alignment with sacred and symphonic tradition, and essential to the study of the trombone in the early 18th century. Padre José Maurício's trombone writing is significant for primarily two reasons: it is at odds with current historical trombone texts, and his insular development in a hegemonic society yielded an individual compositional style.
Date: August 2022
Creator: Davis, Zachariah Tyler
Partner: UNT Libraries
open access

"Untune the Sky": Ten Original Pieces for Microtonal Viola da Gamba with Voice and Electronics

Description: Untune the Sky is a collection of ten original preludes, dances, and songs for microtonal viola da gamba in 7-limit just intonation with voice and live electronics that incorporates elements of Baroque music, traditional Irish dance music, extended just intonation tuning theory, and live electronic audio processing techniques. This thesis thoroughly describes the work and contextualizes its relationship to its historical and contemporary influences. The first sections explain why extended just intonation and viola da gamba were chosen as the central elements of the work. This is followed by a description of the structure, instrumentation, notational conventions, and intended performance practice of the work. The final section contains a musical analysis of the form, harmony, and structure of each piece in the collection. For researchers and interested performers, Appendix A contains a brief catalog of existing microtonal viol repertoire listed with a description of the microtonal techniques used.
Date: August 2022
Creator: Snead, Jonathan Dunnam
Partner: UNT Libraries

Investigation of Room Temperature Sputtering and Laser Annealing of Chalcogen Rich TMDs for Opto-Electronics

Description: Chalcogen-rich transition-metal dichalcogenide (TMD) magnetron sputtering targets were custom manufactured via ball milling and sintering in the interest of depositing p-type chalcogen-rich films. Room temperature radio frequency (RF) magnetron sputtering produced ultra-thin amorphous precursor of WSx and MoSx (where x is between 2-3) on several different substrates. The influence of working pressure on the MoS3 content of the amorphous films was explored with X-ray photoelectron spectroscopy (XPS), while the physical and chemical effects of sputtering were investigated for the WSx target itself. The amorphous precursor films with higher chalcogenide content were chosen for laser annealing, and their subsequent laser annealing induced phase transformations were investigated for the synthesis of polycrystalline 2H-phase semiconducting thin films. The role of laser fluence and the number of laser pulses during annealing on phase transformation and film mobility was determined from Raman spectroscopy and Hall effect measurement, respectively. Hall effect measurements were used to identify carrier type and track mobility between amorphous precursors and crystalline films. The p-type 2H-TMD films demonstrates the ability to produce a scalable processing criterion for quality ultra-thin TMD films on various substrates and in a method which is also compatible for flexible, stretchable, transparent, and bendable substrates.
This item is restricted from view until March 1, 2023.
Date: August 2022
Creator: Gellerup, Branden Spencer
Partner: UNT Libraries
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