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- Genre: Academic theses
- Creators: Goryll, Michael
- Creators: Rogers, Rodney
- Status: Published
Description
One of the challenges in future semiconductor device design is excessive rise of power dissipation and device temperatures. With the introduction of new geometrically confined device structures like SOI, FinFET, nanowires and continuous incorporation of new materials with poor thermal conductivities in the device active region, the device thermal problem is expected to become more challenging in coming years. This work examines the degradation in the ON-current due to self-heating effects in 10 nm channel length silicon nanowire transistors. As part of this dissertation, a 3D electrothermal device simulator is developed that self-consistently solves electron Boltzmann transport equation with 3D energy balance equations for both the acoustic and the optical phonons. This device simulator predicts temperature variations and other physical and electrical parameters across the device for different bias and boundary conditions. The simulation results show insignificant current degradation for nanowire self-heating because of pronounced velocity overshoot effect. In addition, this work explores the role of various placement of the source and drain contacts on the magnitude of self-heating effect in nanowire transistors. This work also investigates the simultaneous influence of self-heating and random charge effects on the magnitude of the ON current for both positively and negatively charged single charges. This research suggests that the self-heating effects affect the ON-current in two ways: (1) by lowering the barrier at the source end of the channel, thus allowing more carriers to go through, and (2) via the screening effect of the Coulomb potential. To examine the effect of temperature dependent thermal conductivity of thin silicon films in nanowire transistors, Selberherr's thermal conductivity model is used in the device simulator. The simulations results show larger current degradation because of self-heating due to decreased thermal conductivity . Crystallographic direction dependent thermal conductivity is also included in the device simulations. Larger degradation is observed in the current along the [100] direction when compared to the [110] direction which is in agreement with the values for the thermal conductivity tensor provided by Zlatan Aksamija.
ContributorsHossain, Arif (Author) / Vasileska, Dragica (Thesis advisor) / Ahmed, Shaikh (Committee member) / Bakkaloglu, Bertan (Committee member) / Goodnick, Stephen (Committee member) / Arizona State University (Publisher)
Created2011
Description
The focus of this study was the first Serbian opera, Na Uranku (At Dawn). It was written by Stanislav Binièki (1872-1942) and was first performed in 1903 at the National Theatre in Belgrade. There were two objectives of this project: (1) a live concert performance of the opera, which produced an audio recording that can be found as an appendix; and, (2) an accompanying document containing a history and an analysis of the work. While Binièki's opera is recognized as an extraordinary artistic achievement, and a new genre of musical enrichment for Serbian music, little had been previously written either about the composer or the work. At Dawn is a romantic opera in the verismo tradition with national elements. The significance of this opera is not only in its artistic expression but also in how it helped the music of Serbia evolve. Early opera settings in Serbia in the mid-nineteenth to early twentieth century did not have the same wealth of history upon which to draw as had existed in the rich operatic oeuvre in Western Europe and Russia. Similarly, conditions for performance were not satisfactory, as were no professional orchestras or singers. Furthermore, audiences were not accustomed to this type of art form. The opera served as an educational instrument for the audience, not only training them to a different type of music but also evolving its national consciousness. Binièki's opera was a foundation on which later generations of composers built. The artistic value of this opera is emphasized. The musical language includes an assimilation of various influences from Western Europe and Russia, properly incorporated into the Serbian musical core. Audience reaction is discussed, a positive affirmation that Binièki was moving in the right direction in establishing a path for the further development of the artistic field of Serbian musical culture. A synopsis of the work as well as the requisite performing forces is also included.
ContributorsMinov, Jana (Author) / Russell, Timothy (Thesis advisor) / Levy, Benjamin (Committee member) / Schildkret, David (Committee member) / Rogers, Rodney (Committee member) / Reber, William (Committee member) / Arizona State University (Publisher)
Created2011
Description
Delirium is a piece for large wind ensemble that synthesizes compositional techniques to generate unique juxtapositions of contrasting musical elements. The piece is about 8:30 long and uses the full complement of winds, brass, and percussion. Although the composition begins tonally, chromatic alterations gradually shift the melodic content outside of the tonal center. In addition to changes in the melody, octatonic, chromatic, and synthetic scales and quartal and quintal harmonies are progressively introduced throughout the piece to add color and create dissonance. Delirium contains four primary sections that are all related by chromatic mediant. The subdivisions of the first part create abrupt transitions between contrasting material, evocative of the symptoms of delirium. As each sub-section progresses, the A minor tonality of the opening gradually gives way to increased chromaticism and dissonance. The next area transitions to C minor and begins to feature octatonic scales, secundal harmonies, and chromatic flourishes more prominently. The full sound of the ensemble then drops to solo instruments in the third section, now in G# minor, where the elements of the previous section are built upon with the addition of synthetic scales and quartal harmonies. The last division, before the recapitulation of the opening material, provides a drastic change in atmosphere as the chromatic elements from before are removed and the tense sound of the quartal harmonies are replaced with quintal sonorities and a more tonal melody. The tonality of this final section is used to return to the opening material. After an incomplete recapitulation, the descending motive that is used throughout the piece, which can be found in measure 61 in the flutes, is inverted and layered by minor 3rds. This inverted figure builds to the same sonority found in measure138, before ending on an F# chord, a minor third away from the A minor tonal center of the opening and where the piece seems like it should end.
ContributorsBell, Jeremy, 1986- (Composer) / Rogers, Rodney (Thesis advisor) / Oldani, Robert (Committee member) / Levy, Benjamin (Committee member) / Arizona State University (Publisher)
Created2011
Description
A systematic approach to composition has been used by a variety of composers to control an assortment of musical elements in their pieces. This paper begins with a brief survey of some of the important systematic approaches that composers have employed in their compositions, devoting particular attention to Pierre Boulez's Structures Ia . The purpose of this survey is to examine several systematic approaches to composition by prominent composers and their philosophy in adopting this type of approach. The next section of the paper introduces my own systematic approach to composition: the Take-Away System. The third provides several musical applications of the system, citing my work, Octulus for two pianos, as an example. The appendix details theorems and observations within the system for further study.
ContributorsHarbin, Doug (Author) / Hackbarth, Glenn (Thesis advisor) / DeMars, James (Committee member) / Etezady, Roshanne, 1973- (Committee member) / Rockmaker, Jody (Committee member) / Rogers, Rodney (Committee member) / Arizona State University (Publisher)
Created2011
Description
During the twentieth-century, the dual influence of nationalism and modernism in the eclectic music from Latin America promoted an idiosyncratic style which naturally combined traditional themes, popular genres and secular music. The saxophone, commonly used as a popular instrument, started to develop a prominent role in Latin American classical music beginning in 1970. The lack of exposure and distribution of the Latin American repertoire has created a general perception that composers are not interested in the instrument, and that Latin American repertoire for classical saxophone is minimal. However, there are more than 1100 works originally written for saxophone in the region, and the amount continues to grow. This Modern Latin American Repertoire for Classical Saxophone: Recording Project and Performance Guide document establishes and exhibits seven works by seven representative Latin American composers.The recording includes works by Carlos Gonzalo Guzman (Colombia), Ricardo Tacuchian (Brazil), Roque Cordero (Panama), Luis Naón (Argentina), Andrés Alén-Rodriguez (Cuba), Alejandro César Morales (Mexico) and Jose-Luis Maúrtua (Peru), featuring a range of works for solo alto saxophone to alto saxophone with piano, alto saxophone with vibraphone, and tenor saxophone with electronic tape; thus forming an important selection of Latin American repertoire. Complete recorded performances of all seven pieces are supplemented by biographical, historical, and performance practice suggestions. The result is a written and audio guide to some of the most important pieces composed for classical saxophone in Latin America, with an emphasis on fostering interest in, and research into, composers who have contributed in the development and creation of the instrument in Latin America.
ContributorsOcampo Cardona, Javier Andrés (Author) / McAllister, Timothy (Thesis advisor) / Spring, Robert (Committee member) / Hill, Gary (Committee member) / Pilafian, Sam (Committee member) / Rogers, Rodney (Committee member) / Gardner, Joshua (Committee member) / Arizona State University (Publisher)
Created2011
Description
This study examined attitudes and perspectives of classroom guitar students toward the reading of staff notation in music. The purpose of this qualitative research was to reveal these perceptions in the student's own words, and compare them to those of orchestra and band students of comparable experience. Forty-seven students from four suburban middle and high schools on the east coast were selected through purposeful sampling techniques. Research instruments included a Musical Background Questionnaire and a thirty-five question Student Survey. Follow-up interviews were conducted with students to clarify or expound upon collected data. Guitar, orchestra, and band teachers were interviewed in order to provide their perspectives on the issues discussed. The Student Survey featured a five-point Likert-type scale, which measured how much students agreed or disagreed with various statements pertaining to their feelings about music, note-reading, or their class at school. Collected data were coded and used to calculate mean scores, standard deviations, and percentages of students in agreement or disagreement with each statement. Interviews were audio recorded and transcribed into a word processing document for analysis. The study found that while a variety of perspectives exist within a typical guitar class, some students do not find note-reading to be necessary for the types of music they desire to learn. Other findings included a perceived lack of relevance toward the classical elements of the guitar programs in the schools, a lack of educational consistency between classroom curricula and private lesson objectives, and the general description of the struggle some guitarists experience with staff notation. Implications of the collected data were discussed, along with recommendations for better engaging these students.
ContributorsWard, Stephen Michael (Author) / Koonce, Frank (Thesis advisor) / Schmidt, Margaret (Thesis advisor) / Buck, Nancy (Committee member) / Rogers, Rodney (Committee member) / McLin, Katherine (Committee member) / Arizona State University (Publisher)
Created2011
Description
There will always be a need for high current/voltage transistors. A transistor that has the ability to be both or either of these things is the silicon metal-silicon field effect transistor (MESFET). An additional perk that silicon MESFET transistors have is the ability to be integrated into the standard silicon on insulator (SOI) complementary metal oxide semiconductor (CMOS) process flow. This makes a silicon MESFET transistor a very valuable device for use in any standard CMOS circuit that may usually need a separate integrated circuit (IC) in order to switch power on or from a high current/voltage because it allows this function to be performed with a single chip thereby cutting costs. The ability for the MESFET to cost effectively satisfy the needs of this any many other high current/voltage device application markets is what drives the study of MESFET optimization. Silicon MESFETs that are integrated into standard SOI CMOS processes often receive dopings during fabrication that would not ideally be there in a process made exclusively for MESFETs. Since these remnants of SOI CMOS processing effect the operation of a MESFET device, their effect can be seen in the current-voltage characteristics of a measured MESFET device. Device simulations are done and compared to measured silicon MESFET data in order to deduce the cause and effect of many of these SOI CMOS remnants. MESFET devices can be made in both fully depleted (FD) and partially depleted (PD) SOI CMOS technologies. Device simulations are used to do a comparison of FD and PD MESFETs in order to show the advantages and disadvantages of MESFETs fabricated in different technologies. It is shown that PD MESFET have the highest current per area capability. Since the PD MESFET is shown to have the highest current capability, a layout optimization method to further increase the current per area capability of the PD silicon MESFET is presented, derived, and proven to a first order.
ContributorsSochacki, John (Author) / Thornton, Trevor J (Thesis advisor) / Schroder, Dieter (Committee member) / Vasileska, Dragica (Committee member) / Goryll, Michael (Committee member) / Arizona State University (Publisher)
Created2011
Description
ABSTRACT The purpose of this study is to demonstrate that stable lipid bilayers can be set up on an array of silicon micropores and can be used as sites for self-inserting ion-channel proteins which can be studied independently of each other. In course of this study an acrylic based holder was designed and machined to ensure leak-free fluidic access to the silicon micropores and physical isolation of the individual array channels. To measure the ion-channel currents, we simulated, designed and manufactured low-noise transimpedance amplifiers and support circuits based on published patch clamp amplifier designs, using currently available surface-mount components. This was done in order to achieve a reduction in size and costs as well as isolation of individual channels without the need for multiplexing of the input. During the experiments performed, stable bilayers were formed across an array of four vertically mounted 30 µm silicon micropores and OmpF porins were added for self insertion in each of the bilayers. To further demonstrate the independence of these bilayer recording sites, the antibiotic Ampicillin (2.5 mM) was added to one of the fluidic wells. The ionic current in each of the wells was recorded simultaneously. Sub-conductance states of Ompf porin were observed in two of the measurement sites. In addition, the conductance steps in the site containing the antibiotic could be clearly seen to be larger compared to those of the unmodified site. This is due to the transient blocking of ion flow through the porin due to translocation of the antibiotic. Based on this demonstration, ion-channel array reconstitution is a potential method for efficient electrophysiological characterization of different types of ion-channels simultaneously as well as for studying membrane permeation processes.
ContributorsRamakrishnan, Shankar (Author) / Goryll, Michael (Thesis advisor) / Thornton, Trevor J (Committee member) / Blain Christen, Jennifer M (Committee member) / Arizona State University (Publisher)
Created2011
Description
In the last few years, significant advances in nanofabrication have allowed tailoring of structures and materials at a molecular level enabling nanofabrication with precise control of dimensions and organization at molecular length scales, a development leading to significant advances in nanoscale systems. Although, the direction of progress seems to follow the path of microelectronics, the fundamental physics in a nanoscale system changes more rapidly compared to microelectronics, as the size scale is decreased. The changes in length, area, and volume ratios due to reduction in size alter the relative influence of various physical effects determining the overall operation of a system in unexpected ways. One such category of nanofluidic structures demonstrating unique ionic and molecular transport characteristics are nanopores. Nanopores derive their unique transport characteristics from the electrostatic interaction of nanopore surface charge with aqueous ionic solutions. In this doctoral research cylindrical nanopores, in single and array configuration, were fabricated in silicon-on-insulator (SOI) using a combination of electron beam lithography (EBL) and reactive ion etching (RIE). The fabrication method presented is compatible with standard semiconductor foundries and allows fabrication of nanopores with desired geometries and precise dimensional control, providing near ideal and isolated physical modeling systems to study ion transport at the nanometer level. Ion transport through nanopores was characterized by measuring ionic conductances of arrays of nanopores of various diameters for a wide range of concentration of aqueous hydrochloric acid (HCl) ionic solutions. Measured ionic conductances demonstrated two distinct regimes based on surface charge interactions at low ionic concentrations and nanopore geometry at high ionic concentrations. Field effect modulation of ion transport through nanopore arrays, in a fashion similar to semiconductor transistors, was also studied. Using ionic conductance measurements, it was shown that the concentration of ions in the nanopore volume was significantly changed when a gate voltage on nanopore arrays was applied, hence controlling their transport. Based on the ion transport results, single nanopores were used to demonstrate their application as nanoscale particle counters by using polystyrene nanobeads, monodispersed in aqueous HCl solutions of different molarities. Effects of field effect modulation on particle transition events were also demonstrated.
ContributorsJoshi, Punarvasu (Author) / Thornton, Trevor J (Thesis advisor) / Goryll, Michael (Thesis advisor) / Spanias, Andreas (Committee member) / Saraniti, Marco (Committee member) / Arizona State University (Publisher)
Created2011
Description
Many of the works of Dominick Argento have been researched and analyzed, but his choral work Evensong: Of Love and Angels s has received limited attention thus far. Written in memoriam for his wife Carolyn Bailey Argento, Evensong draws its musical material from her initials C.B.A. These letters, translated into note names, form a conspicuous head motive that is present in each movement of the work, and it serves multiple functions: as a melodic feature, as the foundation for a twelve-tone row, and as a harmonic base. This paper provides an overview of the work's conception with specific relation to Argento's biographical details, compositional style, and work habits; a brief review of the critical reception of the work; and a succinct analysis of the form and cyclical materials found in each movement.
ContributorsPage, Carrie Leigh, 1980- (Author) / Rogers, Rodney (Thesis advisor) / DeMars, James (Committee member) / Levy, Benjamin (Committee member) / Oldani, Robert (Committee member) / Arizona State University (Publisher)
Created2011