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HgCdTe is the dominant material currently in use for infrared (IR) focal-plane-array (FPA) technology. In this dissertation, transmission electron microscopy (TEM) was used for the characterization of epitaxial HgCdTe epilayers and HgCdTe-based devices. The microstructure of CdTe surface passivation layers deposited either by hot-wall epitaxy (HWE) or molecular beam epitaxy

HgCdTe is the dominant material currently in use for infrared (IR) focal-plane-array (FPA) technology. In this dissertation, transmission electron microscopy (TEM) was used for the characterization of epitaxial HgCdTe epilayers and HgCdTe-based devices. The microstructure of CdTe surface passivation layers deposited either by hot-wall epitaxy (HWE) or molecular beam epitaxy (MBE) on HgCdTe heterostructures was evaluated. The as-deposited CdTe passivation layers were polycrystalline and columnar. The CdTe grains were larger and more irregular when deposited by HWE, whereas those deposited by MBE were generally well-textured with mostly vertical grain boundaries. Observations and measurements using several TEM techniques showed that the CdTe/HgCdTe interface became considerably more abrupt after annealing, and the crystallinity of the CdTe layer was also improved. The microstructure and compositional profiles of CdTe(211)B/ZnTe/Si(211) heterostructures grown by MBE was investigated. Many inclined {111}-type stacking faults were present throughout the thin ZnTe layer, terminating near the point of initiation of CdTe growth. A rotation angle of about 3.5° was observed between lattice planes of the Si substrate and the final CdTe epilayer. Lattice parameter measurement and elemental profiles indicated that some local intermixing of Zn and Cd had taken place. The average widths of the ZnTe layer and the (Cd, Zn)Te transition region were found to be roughly 6.5 nm and 3.5 nm, respectively. Initial observations of CdTe(211)B/GaAs(211) heterostructures indicated much reduced defect densities near the vicinity of the substrate and within the CdTe epilayers. HgCdTe epilayers grown on CdTe(211)B/GaAs(211) composite substrate were generally of high quality, despite the presence of precipitates at the HgCdTe/CdTe interface. The microstructure of HgCdSe thin films grown by MBE on ZnTe/Si(112) and GaSb(112) substrates were investigated. The quality of the HgCdSe growth was dependent on the growth temperature and materials flux, independent of the substrate. The materials grown at 100°C were generally of high quality, while those grown at 140°C had {111}-type stacking defects and high dislocation densities. For epitaxial growth of HgCdSe on GaSb substrates, better preparation of the GaSb buffer layer will be essential in order to ensure that high-quality HgCdSe can be grown.
ContributorsZhao, Wenfeng (Author) / Smith, David J. (Thesis advisor) / McCartney, Martha (Committee member) / Carpenter, Ray (Committee member) / Bennett, Peter (Committee member) / Treacy, Michael J. (Committee member) / Arizona State University (Publisher)
Created2011
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In a conscious effort to combat the low enrollment of women in construction management, a program was created to retain women through a mentorship program - Advancing Women in Construction. A qualitative analysis, facilitated through a grounded theory approach, sought to understand if the program was indeed successful, and what

In a conscious effort to combat the low enrollment of women in construction management, a program was created to retain women through a mentorship program - Advancing Women in Construction. A qualitative analysis, facilitated through a grounded theory approach, sought to understand if the program was indeed successful, and what value did the students derive from the programs and participating in the mentoring process.
ContributorsEicher, Matthew (Author) / Wilkinson, Christine Kajikawa (Thesis advisor) / Calleroz-White, Mistalene (Committee member) / Gibson, Jr., G. Edward (Committee member) / Arizona State University (Publisher)
Created2013
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ABTRACT For decades the United States has tried to increase the number of students pursuing science, technology, engineering, and mathematics (STEM) education and careers. Educators and policy makers continue to seek strategies to increase the number of students in the STEM education pipeline. Public institutions of higher education are involved

ABTRACT For decades the United States has tried to increase the number of students pursuing science, technology, engineering, and mathematics (STEM) education and careers. Educators and policy makers continue to seek strategies to increase the number of students in the STEM education pipeline. Public institutions of higher education are involved in this effort through education and public outreach (EPO) initiatives. Arizona State University opened its largest research facility, the new Interdisciplinary Science and Technology Building IV (ISTB4) in September, 2012. As the new home of the School of Earth & Space Exploration (SESE), ISTB4 was designed to serve the school's dedication to K-12 education and public outreach. This dissertation presents a menu of ideas for revamping the EPO program for SESE. Utilizing the Delphi method, I was able to clarify which ideas would be most supported, and those that would not, by a variety of important SESE stakeholders. The study revealed that consensus exists in areas related to staffing and expansion of free programming, whereas less consensus exist in the areas of fee-based programs. The following most promising ideas for improving the SESE's EPO effort were identified and will be presented to SESE's incoming director in July, 2013: (a) hire a full-time director, theater manager, and program coordinator; (b) establish a service-learning requirement obligating undergraduate SESE majors to serve as docent support for outreach programs; (c) obligate all EPO operations to advise, assist, and contribute to the development of curricula, activities, and exhibits; (d) perform a market and cost analysis of other informational education venues offering similar programming; (3) establish a schedule of fee-based planetarium and film offerings; and (f) create an ISTB4 centric, fee-based package of programs specifically correlated to K12 education standards that can be delivered as a fieldtrip experience.
ContributorsFisher, Richard D. (Author) / Clark, Christopher M. (Thesis advisor) / Kelley, Michael (Committee member) / Glasper, Rufus (Committee member) / Arizona State University (Publisher)
Created2013
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Legislative changes and discussions about the United States falling further and further behind other nations in science, technology, engineering, and math (STEM) achievement are growing. As they grow, STEM instruction in elementary school has earned its place as a national area of interest in education. In the case of Ivory

Legislative changes and discussions about the United States falling further and further behind other nations in science, technology, engineering, and math (STEM) achievement are growing. As they grow, STEM instruction in elementary school has earned its place as a national area of interest in education. In the case of Ivory School District, teachers are being asked to radically change their daily practices by consistently implementing inquiry-based STEM experiences in their classrooms. As such, teachers are being asked to scale a divide between the district expectations and their knowledge and experience. Many fourth grade educators are teachers who have been trained as generalists and typically do not have specific background or experience in the philosophy, instructional strategies, or content associated with STEM. Using a prototype approach, this study aims to understand how such teachers conceptualize STEM instruction and the relationship between their experience and conceptions.
ContributorsKenney, Meghan (Author) / Fischman, Gustavo (Thesis advisor) / Powers, Jeanne (Committee member) / Rasch, Katherine D (Committee member) / Arizona State University (Publisher)
Created2013
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Description
Historically, African American students have been underrepresented in the fields of science, technology, engineering and mathematics (STEM). If African American students continue to be underrepresented in STEM fields, they will not have access to valuable and high-paying sectors of the economy. Despite the number of African Americans in these fields

Historically, African American students have been underrepresented in the fields of science, technology, engineering and mathematics (STEM). If African American students continue to be underrepresented in STEM fields, they will not have access to valuable and high-paying sectors of the economy. Despite the number of African Americans in these fields being disproportionately low, there are still individuals that persist and complete science degrees. The aim of this study was to investigate African American students who excel in science at Arizona State University and examine the barriers and affordances that they encounter on their journey toward graduation. Qualitative research methods were used to address the research question of the study. My methodology included creating a case study to investigate the experiences of eight African American undergraduate college students at Arizona State University. These four male and four female students were excelling sophomores, juniors, or seniors who were majoring in a science field. Two of the males came from lower socioeconomic status (SES) backgrounds, while two of the males were from higher SES backgrounds. The same applied to the four female participants. My research utilized surveys, semistructured interviews, and student observations to collect data that was analyzed and coded to determine common themes and elements that exist between the students. As a result of the data collection opportunities, peer support and financial support were identified as barriers, while, parental support, financial support, peer support, and teacher support were identified as affordances. In analyzing the data, the results indicated that for the student subjects in this study, sex and SES did not have any relationship with the barriers and affordances experienced.
ContributorsBoyce, Quintin (Author) / Scott, Kimberly (Thesis advisor) / Falls, Deanne (Committee member) / Baker, Dale (Committee member) / Arizona State University (Publisher)
Created2012
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Latinas and Latinos are currently underrepresented in terms of our 21st century student academic attainment and workforce, compared to the total U.S. Hispanic population. In a field such as mathematical sciences, Hispanic or Latino U.S. citizenship doctoral recipients only accounted for 3.04% in 2009-2010. While there are various initiatives to

Latinas and Latinos are currently underrepresented in terms of our 21st century student academic attainment and workforce, compared to the total U.S. Hispanic population. In a field such as mathematical sciences, Hispanic or Latino U.S. citizenship doctoral recipients only accounted for 3.04% in 2009-2010. While there are various initiatives to engage underrepresented STEM populations through education, there is a need to give a voice to the experiences of Latinas and Latinos engaged in such programs. This study explored the experiences of seven Arizona State University undergraduate Latina and Latino Joaquín Bustoz Math-Science Honors Program (JBMSHP) participants as well as examined how the program enhanced their math and science learning experiences. Participants attended either a five-week or eight-week program and ranged in attendance from 2006 to 2011. Students were provided an opportunity to begin university mathematics and science studies before graduating high school. Through a demographic survey and one-on-one guided interview, participants shared their personal journey, their experience in the JBMSHP, and their goals. Using grounded theory, a qualitative research approach, this study focuses on the unique experiences of Latina and Latino participants. Four major themes emerged from the analysis of the data. Each participant applied to the program with a foundation in which they sought to challenge themselves academically through mathematics and/or science. Through their involvement it the JBMSHP, participants recognized benefits during and after the program. All participants recognized the value of these benefits and their participation and praised the program. Overall, the JBMSHP provided the students the resources to grow their academic capital and if they chose seek a STEM related bachelor degree. The results of this study emphasize the need to expand the JBMSHP both within Arizona and nationally. In addition, there is a need to explore the other components of their parent center, the Mathematical, Computational and Modeling Sciences Center (MCMSC), to determine if the suggested pipeline, MCMSC Model for Enhancing the Math and Science Experiences of Latinas and Latinos, can positively impact our 21st century workforce and the dire representational need of Latinas and Latinos in STEM fields.
ContributorsEscontrias, Gabriel (Author) / Turner, Caroline S. (Thesis advisor) / Keller, Gary D. (Committee member) / Calleroz White, Mistalene D. (Committee member) / Arizona State University (Publisher)
Created2012
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Description
Academia is not what it used to be. In today’s fast-paced world, requirements

are constantly changing, and adapting to these changes in an academic curriculum

can be challenging. Given a specific aspect of a domain, there can be various levels of

proficiency that can be achieved by the students. Considering the wide array

Academia is not what it used to be. In today’s fast-paced world, requirements

are constantly changing, and adapting to these changes in an academic curriculum

can be challenging. Given a specific aspect of a domain, there can be various levels of

proficiency that can be achieved by the students. Considering the wide array of needs,

diverse groups need customized course curriculum. The need for having an archetype

to design a course focusing on the outcomes paved the way for Outcome-based

Education (OBE). OBE focuses on the outcomes as opposed to the traditional way of

following a process [23]. According to D. Clark, the major reason for the creation of

Bloom’s taxonomy was not only to stimulate and inspire a higher quality of thinking

in academia – incorporating not just the basic fact-learning and application, but also

to evaluate and analyze on the facts and its applications [7]. Instructional Module

Development System (IMODS) is the culmination of both these models – Bloom’s

Taxonomy and OBE. It is an open-source web-based software that has been

developed on the principles of OBE and Bloom’s Taxonomy. It guides an instructor,

step-by-step, through an outcomes-based process as they define the learning

objectives, the content to be covered and develop an instruction and assessment plan.

The tool also provides the user with a repository of techniques based on the choices

made by them regarding the level of learning while defining the objectives. This helps

in maintaining alignment among all the components of the course design. The tool

also generates documentation to support the course design and provide feedback

when the course is lacking in certain aspects.

It is not just enough to come up with a model that theoretically facilitates

effective result-oriented course design. There should be facts, experiments and proof

that any model succeeds in achieving what it aims to achieve. And thus, there are two

research objectives of this thesis: (i) design a feature for course design feedback and

evaluate its effectiveness; (ii) evaluate the usefulness of a tool like IMODS on various

aspects – (a) the effectiveness of the tool in educating instructors on OBE; (b) the

effectiveness of the tool in providing appropriate and efficient pedagogy and

assessment techniques; (c) the effectiveness of the tool in building the learning

objectives; (d) effectiveness of the tool in document generation; (e) Usability of the

tool; (f) the effectiveness of OBE on course design and expected student outcomes.

The thesis presents a detailed algorithm for course design feedback, its pseudocode, a

description and proof of the correctness of the feature, methods used for evaluation

of the tool, experiments for evaluation and analysis of the obtained results.
ContributorsRaj, Vaishnavi (Author) / Bansal, Srividya (Thesis advisor) / Bansal, Ajay (Committee member) / Mehlhase, Alexandra (Committee member) / Arizona State University (Publisher)
Created2018
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In recent years, women have made significant advances in traditionally male occupations. Despite this progress, women are still underrepresented in many science, technology, engineering, and mathematics (STEM) fields. Social cognitive career theory (SCCT) and the model of Achievement Related Choices are two widely accepted career development theories. Both theories highlight

In recent years, women have made significant advances in traditionally male occupations. Despite this progress, women are still underrepresented in many science, technology, engineering, and mathematics (STEM) fields. Social cognitive career theory (SCCT) and the model of Achievement Related Choices are two widely accepted career development theories. Both theories highlight the importance of self-efficacy and personal factors in career development; yet, neither of them has considered the predictive power of a specific outcome expectation, anticipated work family conflict (AWFC), in relation to the career development of men and women in STEM undergraduate programs. The purpose of this study was to assess the incremental validity of AWFC over and above that of self-efficacy and role salience, in predicting educational and occupational aspirations of undergraduate students in STEM programs at a large southwestern university. The study provides evidence that the factor structure of the AWFC scale does not hold up with the undergraduate population, and this finding was seen as reason to combine the AWFC subscales into one composite score. In a hierarchical multiple regression higher levels of STEM self-efficacy predicted higher intentions to persist in STEM. Role salience, AWFC, and the gender-AWFC interaction were not significantly related to intentions to persist. Although the study does not provide evidence for the incremental validity of AWFC, it does suggest that work-family balance considerations that have been observed in mature STEM populations may not yet be salient for students at the undergraduate level.
ContributorsDawson, Amy (Author) / Bernstein, Bianca L (Thesis advisor) / Homer, Judith (Committee member) / Spanierman, Lisa (Committee member) / Arizona State University (Publisher)
Created2014
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In the United States, there is a national agenda to increase the number of qualified science, technology, engineering, and maths (STEM) professionals and a movement to promote science literacy among the general public. This project explores the association between formal human evolutionary biology education (HEB) and high school science class

In the United States, there is a national agenda to increase the number of qualified science, technology, engineering, and maths (STEM) professionals and a movement to promote science literacy among the general public. This project explores the association between formal human evolutionary biology education (HEB) and high school science class enrollment, academic achievement, interest in a STEM degree program, motivation to pursue a STEM career, and socioscientific decision–making for a sample of students enrolled full–time at Arizona State University. Given a lack of a priori knowledge of these relationships, the Grounded Theory Method was used and was the foundation for a mixed–methods analysis involving qualitative and quantitative data from one–on–one interviews, focus groups, questionnaires, and an online survey. Theory development and hypothesis generation were based on data from 44 students. The survey instrument, developed to test the hypotheses, was completed by 486 undergraduates, age 18–22, who graduated from U.S. public high schools. The results showed that higher exposure to HEB was correlated with greater high school science class enrollment, particularly for advanced biological science classes, and that, for some students, HEB exposure may have influenced their enrollment, because the students found the content interesting and relevant. The results also suggested that students with higher K–12 HEB exposure felt more prepared for undergraduate science coursework. There was a positive correlation between HEB exposure and interest in a STEM degree and an indirect relationship between higher HEB exposure and motivation to pursue a STEM career. Regarding a number of socioscientific issues, including but not limited to climate change, homosexuality, and stem cell research, students' behaviors and decision–making more closely reflected a scientific viewpoint—or less–closely aligned to a religion–based perspective—when students had greater HEB exposure, but this was sometimes contingent on students' lifetime exposure to religious doctrine and acceptance of general evolution or human evolution. This study has implications for K–12 and higher education and justifies a paradigm shift in evolution education research, such that more emphasis is placed on students' interests, perceived preparation for continued learning, professional goals and potential contributions to society rather than just their knowledge and acceptance.
ContributorsSchrein, Caitlin M (Author) / Toon, Richard (Thesis advisor) / Johanson, Donald (Thesis advisor) / Hackett, Edward (Committee member) / Molina-Walters, Debra (Committee member) / Arizona State University (Publisher)
Created2014
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An underrepresentation of females exists in the STEM fields. In order to tackle this issue, work begins early in the education of young women to ensure they are interested and have the confidence to gain a career in the STEM fields. It is important to engage girls in STEM opportunities

An underrepresentation of females exists in the STEM fields. In order to tackle this issue, work begins early in the education of young women to ensure they are interested and have the confidence to gain a career in the STEM fields. It is important to engage girls in STEM opportunities in and out of school to ignite their interest and build their confidence. Brigid Barron's learning ecology perspective shows that girls pursuing STEM outside of the classroom is critical to their achievement in the STEM pipeline. This study investigated the impact after-school STEM learning opportunities have on middle school girls by investigating (a) how the length of engagement in after-school programs can affect the confidence of female students in their science and math abilities; (b) how length of engagement in after-school programs can affect the interest of female students in attaining a career in STEM; (c) how length of engagement in after-school programs can affect interest in science and math classes; and (d) how length of engagement can affect how female students' view gender parity in the STEM workforce. The major findings revealed no statistical significance when comparing confidence in math or science abilities or the perception that gender plays a role in attaining a career in STEM. The findings revealed statistical significance in the areas when comparing length of engagement in the girls' interest in their math class and attaining a career in three of the four STEM fields: science, technology, and engineering. The findings showed that multiple terms of engagement in the after-school STEM programs appear to be an effective catalyst to maintain the interest of girls pursuing STEM-related careers, in addition to allowing their interest in a topic to provide a new lens for the way they see their math work during the school day. The implications of this study show that schools must engage middle school girls who are interested in STEM in a multitude of settings, including outside of the classroom in order to maintain engagement in the STEM pipeline.
ContributorsCupp, Garth Meichel (Author) / Spencer, Dee Ann (Thesis advisor) / Appleton, Nicholas (Committee member) / Schauer, David K (Committee member) / Arizona State University (Publisher)
Created2015