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  Access Rights: Public
  Partner: UNT Libraries
 Decade: 1990-1999
 Collection: UNT Theses and Dissertations
Adhesion/diffusion barrier layers for copper integration: carbon-silicon polymer films and tantalum substrates

Adhesion/diffusion barrier layers for copper integration: carbon-silicon polymer films and tantalum substrates

Date: December 1999
Creator: Chen, Li
Description: The Semiconductor Industry Association (SIA) has identified the integration of copper (Cu) with low-dielectric-constant (low-k) materials as a critical goal for future interconnect architectures. A fundamental understanding of the chemical interaction of Cu with various substrates, including diffusion barriers and adhesion promoters, is essential to achieve this goal. The objective of this research is to develop novel organic polymers as Cu/low-k interfacial layers and to investigate popular barrier candidates, such as clean and modified tantalum (Ta) substrates. Carbon-silicon (C-Si) polymeric films have been formed by electron beam bombardment or ultraviolet (UV) radiation of molecularly adsorbed vinyl silane precursors on metal substrates under ultra-high vacuum (UHV) conditions. Temperature programmed desorption (TPD) studies show that polymerization is via the vinyl groups, while Auger electron spectroscopy (AES) results show that the polymerized films have compositions similar to the precursors. Films derived from vinyltrimethyl silane (VTMS) are adherent and stable on Ta substrates until 1100 K. Diffusion of deposited Cu overlayers is not observed below 800 K, with dewetting occurred only above 400 K. Hexafluorobenzene moieties can also be incorporated into the growing film with good thermal stability. Studies on the Ta substrates demonstrate that even sub-monolayer coverages of oxygen or carbide on polycrystalline ...
Contributing Partner: UNT Libraries
An Analysis of the Ability of an Instrument to Measure Quality of Library Service and Library Success

An Analysis of the Ability of an Instrument to Measure Quality of Library Service and Library Success

Date: December 1999
Creator: Landrum, Hollis T.
Description: This study consisted of an examination of how service quality should be measured within libraries and how library service quality relates to library success. A modified version of the SERVQUAL instrument was evaluated to determine how effectively it measures library service quality. Instruments designed to measure information center success and information system success were evaluated to determine how effectively they measure library success and how they relate to SERVQUAL. A model of library success was developed to examine how library service quality relates to other variables associated with library success. Responses from 385 end users at two U.S. Army Corps of Engineers libraries were obtained through a mail survey. Results indicate that library service quality is best measured with a performance-based version of SERVQUAL, and that measuring importance may be as critical as measuring expectations for management purposes. Results also indicate that library service quality is an important factor in library success and that library success is best measured with a combination of SERVQUAL and library success instruments. The findings have implications for the development of new instruments to more effectively measure library service quality and library success as well as for the development of new models of library service ...
Contributing Partner: UNT Libraries
Asleep in the Arms of God

Asleep in the Arms of God

Date: December 1999
Creator: Clay, Kevin M.
Description: A work of creative fiction in the form of a short novel, Asleep in the Arms of God is a limited-omniscient and omniscient narrative describing the experiences of a man named Wafer Roberts, born in Jack County, Texas, in 1900. The novel spans the years from 1900 to 1925, and moves from the Keechi Valley of North Texas, to Fort Worth and then France during World War One, and back again to the Keechi Valley. The dissertation opens with a preface, which examines the form of the novel, and regional and other aspects of this particular work, especially as they relate to the postmodern concern with fragmentation and conditional identity. Wafer confronts in the novel aspects of his own questionable history, which echo the larger concern with exploitative practices including racism, patriarchy, overplanting and overgrazing, and pollution, which contribute to and climax in the postmodern fragmentation. The novel attempts to make a critique of the exploitative rage of Western civilization.
Contributing Partner: UNT Libraries
Benchmarks in American Higher Education: Selected Approaches for Distance Education Copyright and Intellectual Property Policies

Benchmarks in American Higher Education: Selected Approaches for Distance Education Copyright and Intellectual Property Policies

Date: December 1999
Creator: Smith, Kenneth D.
Description: An evaluation of American higher education distance education programs was conducted to explore how they approach intellectual property, copyright and information sharing/antitrust policy concerns for Internet-based programs. An evaluation of the current status of distance education and Internet-based training in higher education was conducted through a pilot study that included a random sample of 223 accredited institutions. Seventy-seven institutions responded to a survey, of which there were 14 Research I&II, 17 Doctorate I&II, and 46 Master's I&II institutions included in this study. A review of institutional policy approaches for these 77 institutions was conducted via Internet Web site and bulletin review. A multiple-case study was also conducted which included 10 of the top 30 accredited distance education institutions in America. Policy approaches were examined for all institutions and differences were discussed for public and private institutions as well as the following Carnegie Class institutions- Research I&II, Doctorate I&II and Master's I&II. Ten percent of all institutions that responded to the pilot study developed a written policy addressing antitrust/information-sharing concerns. Additionally, the data indicated that 22% of institutions in these Carnegie Class ranges published copyright and intellectual property policy on their institutions' Internet Web site. Ninety percent of the institutions in ...
Contributing Partner: UNT Libraries
Cassette Systems for Creating Intergeneric Hybrid ATCases

Cassette Systems for Creating Intergeneric Hybrid ATCases

Date: December 1999
Creator: Simpson, Luci N.
Description: Cassette systems for creating intergeneric hybrid ATCases were constructed. An MluI restriction enzyme site was introduced at the carbamoylphosphate binding site within the pyrB genes of both Pseudomonas putida and Escherichia coli. Two hybrids, E. coli pyrB polar domain fused with P. putida pyrB equatorial domain and P. putida pyrB polar domain fused with E. coli pyrB equatorial domain, are possible. The intergeneric E. coli-P. putida hybrid pyrB gene was constructed and found to encode an active ATCase which complemented an E. coli Pyr- strain. These hybrids are useful for kinetic and expression studies of ATCase in E. coli.
Contributing Partner: UNT Libraries
Classification of toolmark surfaces on zipper teeth

Classification of toolmark surfaces on zipper teeth

Date: December 1999
Creator: Jacobsen, Dawn
Description: This study proposes the classification of the toolmark under the heads of zipper teeth as a subclass characteristic as outlined by the Association of Firearm and Toolmark Examiners (AFTE). Two separate cases in which zipper teeth were found at crime scenes prompted this study. Brass zipper teeth manufactured by YKK were taken from 20 pairs of jeans and studied using a Reichert comparison microscope at 4X power. Photographs were taken and over 750 comparisons made. It was found that the toolmarks on each side on the 20 zippers were unique and independent of all other sides. The observations made in this study indicate that classifying zipper teeth toolmarks as a subclass characteristic is valid.
Contributing Partner: UNT Libraries
The effects of a tactile prompting device on the requesting behavior of a child with autism

The effects of a tactile prompting device on the requesting behavior of a child with autism

Date: December 1999
Creator: Russo, Lori A.
Description: In the present experiment, a remote control tactile prompting device (RCT) was utilized to prompt a child with autism to recruit teacher models and play suggestions. A multiple baseline and reversal was used to assess the effects of the RCT across three play contexts. The results showed increases in the number of requests for models and suggestions as well as increases in the duration of interactive play between the child and therapist, the number of contextual statements emitted by the child, and the topography and contexts of the play behaviors emitted by the child. Findings are discussed in terms of the effectiveness and generality of the RCT and the issue of teaching a child to recruit versus teaching a child activity-specific behaviors.
Contributing Partner: UNT Libraries
The Effects of Age, Sex, and Class Stratification and the Use of Health Care Services among Older Adults in the United Kingdom

The Effects of Age, Sex, and Class Stratification and the Use of Health Care Services among Older Adults in the United Kingdom

Date: December 1999
Creator: Carter, Holly R.
Description: As the population ages, providing health services for the growing number of older people will become an increasingly difficult problem. In countries where the health services are provided by the government, these problems are involved with complicated issues of finance and ethics. This is the case of the National Health Service, the government institution providing health care for the citizens of the United Kingdom. Knowing what social factors influence health care usage can be a link to match usage and funding. Literature has shown that health care utilization can be predicted by social factors, as well as the medical model, and from this orientation social variables were drawn from the 1994 General Household Survey. Social factors were analyzed to determine relationships that exist between certain types of health care use and these factors. Age, sex, and class, the three main factors shown in literature to affect usage, were then analyzed to determine if services are allocated on the basis of these factors or the basis of need from illness and disability. Results of the study show that of the predisposing variables, age, sex, and class, are associated with most types of health care use. From the enabling variables, both source ...
Contributing Partner: UNT Libraries
The Effects of Shaping and Instruction-based Procedures on Behavioral Variability during Acquisition and Extinction

The Effects of Shaping and Instruction-based Procedures on Behavioral Variability during Acquisition and Extinction

Date: December 1999
Creator: McCary, Donald
Description: This study examined effects of two response acquisition procedures on topography of responding using the revealed operant technique and compared results to previous experiments on this topic. Subjects emitted 100 repetitions each of 4 response patterns on a continuous schedule of reinforcement. A 30-min extinction condition followed acquisition. One group of subjects learned the first response through a series of shaping steps designed to reduce acquisition variability. Another group of subjects was instructed in the correct response topography and was told there was no penalty for attempting other sequences. The first group of subjects produced high variability during extinction despite reduced variability in acquisition. The second group of subjects responded with moderate to high variability during extinction and little variability during acquisition. Most extinction responses for the first group were variations of the last pattern reinforced. Most extinction responses for the second group were repetitions of the last pattern reinforced.
Contributing Partner: UNT Libraries
Elasticity of money as a reinforcer: Assessing multiple compositions of unit price

Elasticity of money as a reinforcer: Assessing multiple compositions of unit price

Date: December 1999
Creator: Viken, Kjetil
Description: Behavioral economics is the integration of concepts from micro-economics into behavior analysis. Most of the research in behavioral economics has been done with non-human subjects and with drugs as reinforcers. This study represents an extension of previous research to assess money as a reinforcer with humans as subjects. The participants in this study solved math problems to earn money at various unit prices. Results indicate that demand of money adhered to the law of demand in that consumption decreased as unit prices increased. An underlying assumption is that consumption should be equivalent at different compositions of unit price. Replications of either the same or different compositions of unit price indicated that there were some discrepancies in consumption in this study.
Contributing Partner: UNT Libraries
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