Assumindo elétrons e buracos se movimentando em suas bandas próprias e centros de recombinação independente para ambos, Hughes e Sokel calcularam as características e distribuição de cargas para o oxido de chumbo (PbO) quando este se encontra sob radiação. O cálculo também inclui a corrente de difusão e segundo os autores, esta possui um importante papel em muitos aspectos. Neste trabalho a característica para o PbO foi recalculado sem considerar a contribuição da corrente de difusão e essencialmente foi obtido o mesmo resultado. Foram desenvolvidos aproximações para baixo e alto campo. Em seguida, foram assumidos iguais parâmetros para ambos portadores (isto é, iguais mobilidades, tempos de captura, coeficientes de recombinação e densidades de centros de captura) e obtido as características para 18 combinações de três conjuntos de parâmetros convenientemente definidos. Aproximações de campo baixo e campo alto foram também derivadas para este caso / Assuming electron and hole bands and independent recombination centers or both carriers, Hughes and Sokel calculated the characteristics and charge distributions for lead oxide PbO under irradiation. The calculation also included the diffusion current and it was asserted that such a current was important in some aspects. In this work the characteristic for PbO was recalculated without the diffusion component and essentially the same result was obtained. Side this; approximations were derived for low and high fields. Next, assuming equal parameters for both carriers (that is, equal mobilities, trapping times, recombination rates and density of trap), characteristics were obtained for 18 combinations of three conveniently defined set of parameters. Low and high field approximation were also derived for this case

Li Yiu-Ching. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references (p. 123-132). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.

Sze Tung Po Eric. / "Mar 2000." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2000. / Includes bibliographical references. / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.

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by Kwok Chiu Nga. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1998. / Includes bibliographical references (leaves 1-3 (4th gp.)). / Abstract also in Chinese. / TABLE OF CONTENTS --- p.i / ABSTRACT --- p.iv / 摘要 --- p.vi / LIST OF FIGURES --- p.vii / LIST OF TABLES --- p.x / ABBREVIATION --- p.xi / Chapter CHAPTER ONE --- RESEARCH BACKGROUND / Chapter 1.1 --- Introduction --- p.1 / Chapter 1.1.1 --- Alkaloids --- p.1 / Chapter 1.1.2 --- Diterpenoid alkaloids --- p.2 / Chapter 1.1.3 --- Aconitine-type alkaloids --- p.2 / Chapter 1.1.4 --- Toxicity --- p.4 / Chapter 1.1.5 --- Safety concerns --- p.4 / Chapter 1.2 --- Summary of the Previous Work --- p.8 / Chapter 1.3 --- Objectives and Outline of the Present Work --- p.13 / Chapter CHAPTER TWO --- INSTRUMENTATION AND EXPERIMENTAL / Chapter 2.1 --- Instrumentation --- p.15 / Chapter 2.1.1 --- High performance liquid chromatography (HPLC) --- p.15 / Chapter 2.1.2 --- Triple-stage quadrupole (TSQ) mass spectrometer --- p.17 / Chapter 2.1.2.1 --- Atmospheric pressure chemical ionization (APCI) --- p.17 / Chapter 2.1.2.2 --- Electrospray ionization (ESI) --- p.20 / Chapter 2.1.2.3 --- Quadrupole system --- p.20 / Chapter 2.1.2.4 --- Ion detection system --- p.22 / Chapter 2.1.2.5 --- Data system --- p.22 / Chapter 2.2 --- Experimental --- p.22 / Chapter 2.2.1 --- Sample and reagents --- p.22 / Chapter 2.2.2 --- Sample preparation --- p.23 / Chapter 2.2.3 --- High performance liquid chromatography conditions --- p.23 / Chapter 2.2.4 --- Mass spectrometry conditions --- p.25 / Chapter 2.2.4.1 --- Atmospheric pressure chemical ionization conditions --- p.25 / Chapter 2.2.4.2 --- Electrospray ionization conditions --- p.25 / Chapter CHAPTER THREE --- SELECTION AND OPTIMIZATION OF HPLC/MS METHOD / Chapter 3.1 --- Introduction --- p.26 / Chapter 3.2 --- Experimental --- p.29 / Chapter 3.3 --- Results and Discussion --- p.29 / Chapter 3.3.1 --- Triethylamine concentration --- p.31 / Chapter 3.3.2 --- Ammonium acetate concentration --- p.34 / Chapter 3.3.3 --- Acetic acid concentration --- p.37 / Chapter 3.3.4 --- HPLC/MS interface --- p.40 / Chapter 3.3.5 --- MS/MS conditions --- p.40 / Chapter 3.4 --- Conclusions --- p.43 / Chapter CHAPTER FOUR --- DETERMINATION OF ACONITINE-TYPE ALKALOIDS IN ACONITE ROOTS / Chapter 4.1 --- Introduction --- p.48 / Chapter 4.2 --- Experimental --- p.48 / Chapter 4.3 --- Results and Discussion --- p.50 / Chapter 4.3.1 --- Selection of internal standard --- p.50 / Chapter 4.3.2 --- Method validation --- p.50 / Chapter 4.3.2.1 --- Precision of measurement --- p.50 / Chapter 4.3.2.2 --- Accuracy of measurement --- p.50 / Chapter 4.3.2.3 --- Limits of detection and quantitation --- p.58 / Chapter 4.3.3 --- Determination of aconitine-type alkaloids in aconite roots --- p.58 / Chapter 4.4 --- Conclusions --- p.60 / Chapter CHAPTER FIVE --- CONCLUSIONS AND FUTURE WORK / Chapter 5.1 --- Conclusions --- p.67 / Chapter 5.2 --- Future Work --- p.68 / ACKNOWLEDGMENT --- p.A1 / APPENDIX --- p.A2 / REFERENCES --- p.R1

Ko Ka Lung. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references. / Abstracts in English and Chinese. / Title page --- p.i / Abstract (English) --- p.ii / Abstract (Chinese) --- p.iii / Acknowledgement --- p.iv / Declaration --- p.v / Table of Content --- p.vi / List of Figure --- p.viii / Chapter 1. --- INTRODUCTION --- p.1 / Chapter 1.1 --- Matrix-assisted Laser Desorption / Ionization (MALDI) --- p.2 / Chapter 1.1.1 --- Evolution of Matrix-assisted laser desorption / ionization (MALDI) --- p.2 / Chapter 1.1.1.1 --- Lasers --- p.3 / Chapter 1.1.1.2 --- Matrices --- p.3 / Chapter 1.1.1.3 --- Sample preparation --- p.4 / Chapter 1.1.1.4 --- Desorption --- p.6 / Chapter 1.1.1.5 --- Ionization --- p.7 / Chapter 1.2 --- Fourier Transform Ion Cyclotron Resonance Mass Spectrometry with MALDI (FTICR-MS) --- p.9 / Chapter 1.2.1 --- History of Fourier Transform Ion Cyclotron Resonance Mass Spectrometry --- p.9 / Chapter 1.2.2 --- Basics of FTICR-MS --- p.11 / Chapter 1.2.3 --- FTICR couple with external ionization source --- p.15 / Chapter 1.2.4 --- Coupling of MALDI to FTICR --- p.16 / Chapter 1.3 --- Problems encountered on the coupling of MALDI to FTICR-MS --- p.17 / Chapter 1.4 --- Outline of present work --- p.19 / Chapter 2 --- SIMULATION METHOD --- p.20 / Chapter 2.1 --- Overview of the ion optics simulation --- p.21 / Chapter 2.2 --- History of SIMION Program --- p.22 / Chapter 2.3 --- Basics and theory of SIMION version 6.0 --- p.24 / Chapter 2.4 --- Simulation method --- p.26 / Chapter 2.4.1 --- Creating potential array --- p.27 / Chapter 2.4.2 --- User program --- p.29 / Chapter 2.4.3 --- Ion definition parameter --- p.31 / Chapter 2.4.4 --- Trajectories quality panel --- p.33 / Chapter 2.4.5 --- Data recording --- p.36 / Chapter 3 --- OPTIMIZATION OF RF-ONLY HEXAPOLE UNDER PULSE GAS CONDITION --- p.37 / Chapter 3.1 --- Introduction --- p.38 / Chapter 3.2 --- Simulation conditions --- p.39 / Chapter 3.3 --- Results and discussion --- p.40 / Chapter 3.3.1 --- rf-frequency (w) --- p.41 / Chapter 3.3.2 --- rf voltage (Vo-p) --- p.44 / Chapter 3.3.3 --- Pulse gas pressure(po) --- p.47 / Chapter 3.3.4 --- Trapping potential (VT) --- p.49 / Chapter 3.3.5 --- Effect of space charge --- p.53 / Chapter 3.4 --- Conclusions --- p.60 / Chapter 4 --- OPTIMIZATION OF DIFFERENT HEXAPOLE-BASED INTERFACES FOR PRE-TRAPPING COOLING --- p.61 / Chapter 4.1 --- Introduction --- p.62 / Chapter 4.2 --- Simulation conditions --- p.63 / Chapter 4.3 --- Results and discussion --- p.66 / Chapter 4.3.1 --- Static medium pressure interface --- p.66 / Chapter 4.3.1.1 --- Effect of pressure --- p.66 / Chapter 4.3.1.2 --- Effect of space charge --- p.70 / Chapter 4.3.2 --- Differential pressure model (Skimmer-based) --- p.73 / Chapter 4.3.2.1 --- Effect of pressure --- p.73 / Chapter 4.3.2.2 --- Effect of space charge --- p.76 / Chapter 4.3.3 --- A comparison of the optimal operating conditions for the three proposed interfaces --- p.81 / Chapter 4.3.4 --- Comparison of the theoretical results amd the experimental results --- p.83 / Chapter 4.4 --- Conclusion --- p.84 / Chapter 5 --- CONCLUSIONS --- p.85 / Chapter 5.1 --- Conclusions --- p.86 / REFERENCES --- p.R1 / APPENDIX --- p.A1

<p>Ambient ionization mass spectrometry enables rapid <i>in-situ</i> analysis of a plethora of analytes that are relevant to the forensic and defense communities. As the arsenal of ambient ionization techniques, aimed at solving specific targeted problems, continues to expand, the adoption of these techniques into non-academic settings has been relatively slow. At times, although the technique can provide answers in a more rapid and cheaper manner, the technique does not pass all of the required legal rules for a particular analysis when dealing with forensic evidence. This can be demonstrated with the rapid detection of drugs by paper spray ionization mass spectrometry. Paper spray ionization mass spectrometry can have drugs deposited onto the paper substrate, the paper can wipe a surface for trace analytes, and there are commercial and automated ionization sources for this process. While analysis by paper spray is rapid, the Scientific Working Group for the Analysis of Seized Drugs (SWGDRUG) states that a minimum of two instrumental techniques need to be utilized. Utilizing paper substrates that have nanoparticles embedded for surface enhanced Raman spectroscopy, that can also be utilized for paper spray ionization mass spectrometry, makes ambient ionization more appealing as it completes that first legal requirement. </p> <p>Other times, the slow adoption of these new ambient ionization techniques is due to specific communities not being aware of ambient ionization, and specific applications have not yet been demonstrated. Swab touch spray ionization mass spectrometry follows similar processes as paper spray ionization, as the swab acts both as the sampling substrate and the ionization source and can swab for analytes in a manner where the paper substrate may be damaged and unable to perform the ionization for analysis. This can be seen for the swabbing of organic gunshot residues and explosives, both of which current methods already use a swab for sampling but then need lengthy extraction techniques. The applicability of paper spray ionization and swab touch spray ionization for these forensic and defense analyses is only furthered by the fact that they both couple extremely well with portable mass spectrometers for analysis in the field.</p> <p>There are also many fields that ambient ionization is just starting to take its place in the analytical toolbox. Two such defense fields that are just beginning to expand into ambient ionization are the analysis of pyrotechnics and microelectronics. Pyrolysis gas-chromatography mass spectrometry methods have been developed and utilized for environmental tests for pyrotechnic formulation, but they are slow and there is an abundance of cleaning steps between analyses to prevent carry over and contamination. Using paper and swabs as the collection device and ionization source for environmental analysis of these pyrotechnics allow for them to be functioned at ambient conditions at the scale at which will be utilized in the field by the Warfighter. Similarly, authenticating microelectronics by desorption electrospray ionization mass spectrometry removes the subjectivity of the current methods, while rendering the integrated circuit intact enabling future use if deemed as a genuine part. By taking slower or more subjective tests, in a field that has not utilized ambient ionization heavily in the past and adding these new capabilities to their tool chest expands the acceptance and future applications of the technique.</p> <p>As acceptance and utilization of ambient ionization grows, the next generation of scientists need to have hands on training in these techniques. Through the development of new teaching laboratories that couple both the fundamentals of the technique at hand, while also examining an interesting application to better engage the students, a number of laboratory exercises have been developed. The creation of new laboratory exercise utilizing the next generation of instrumentation and analytical techniques is vital for the future and rapid application of these techniques. The work discussed herein chronicles the utilization and demonstration of ambient ionization mass spectrometry in monitoring clandestine activities, supporting the Warfighter, and redeveloping chemical laboratory education. </p>

by Cheng Sau Wan. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1996. / Includes bibliographical references (leaves [72]-[76]). / TABLE OF CONTENTS --- p.i / ABSTRACT --- p.iv / LIST OF FIGURES --- p.vi / LIST OF TABLES --- p.x / Chapter CHAPTER ONE --- RESEARCH BACKGROUND --- p.1 / Chapter 1.1 --- Introduction --- p.1 / Chapter 1.2 --- Matrix-assisted laser desorption / ionization mass spectrometry (MALDI) --- p.2 / Chapter 1.2.1 --- Laser desorption methods --- p.2 / Chapter 1.2.2 --- The matrix --- p.3 / Chapter 1.2.2.1 --- Role of the matrix --- p.3 / Chapter 1.2.2.2 --- Features of the matrix --- p.4 / Chapter 1.2.3 --- Mechanisms of ion formation --- p.6 / Chapter 1.2.3.1 --- Desorption process(es) --- p.6 / Chapter 1.2.3.2 --- Ionization process(es) --- p.7 / Chapter 1.3 --- Sequencing of DNA --- p.8 / Chapter 1.3.1 --- DNA sequencing procedure --- p.10 / Chapter 1.3.1.1 --- Generation of the nested set of DNA molecules --- p.11 / Chapter 1.3.1.2 --- Sequence analysis --- p.11 / Chapter 1.3.2 --- MALDI-TOF-MS as a DNA sequencing tool --- p.12 / Chapter 1.3.3 --- MALDI analysis of oligonucleotides --- p.14 / Chapter 1.4 --- Outline of the present work --- p.16 / Chapter CHAPTER TWO --- INSTRUMENTATION AND EXPERIMENTAL --- p.18 / Chapter 2.1 --- Time-of-flight mass spectrometry (TOF-MS) --- p.18 / Chapter 2.1.1 --- Linear time-of-flight mass spectrometry --- p.18 / Chapter 2.1.2 --- Reflectron time-of-flight mass spectrometry --- p.21 / Chapter 2.1.3 --- Ion detection --- p.22 / Chapter 2.1.4 --- Vacuum system --- p.22 / Chapter 2.2 --- Instrumentation --- p.24 / Chapter 2.2.1 --- The laser system --- p.24 / Chapter 2.2.2 --- Ion source and vacuum system --- p.24 / Chapter 2.2.3 --- Flight tube and reflector --- p.27 / Chapter 2.2.4 --- The detector --- p.28 / Chapter 2.2.5 --- Data acquisition and computer control --- p.28 / Chapter 2.3 --- Experimental --- p.29 / Chapter 2.3.1 --- Sample preparation --- p.29 / Chapter 2.3.2 --- Mass spectrometric analysis --- p.30 / Chapter CHAPTER THREE --- USE OF AMMONIUM SALTS AS CO-MATRICES --- p.32 / Chapter 3.1 --- Introduction --- p.32 / Chapter 3.2 --- Experimental --- p.35 / Chapter 3.3 --- Results and Discussion --- p.36 / Chapter 3.3.1 --- Effects of counter-anions --- p.36 / Chapter 3.3.2 --- Effects of matrix materials --- p.40 / Chapter 3.4 --- Conclusions --- p.43 / Chapter CHAPTER FOUR --- USE OF POTASSIUM SALTS AS CO-MATRICES --- p.44 / Chapter 4.1 --- Introduction --- p.44 / Chapter 4.2 --- Experimental --- p.44 / Chapter 4.3 --- Results and Discussion --- p.44 / Chapter 4.3.1 --- Adduct formation --- p.49 / Chapter 4.3.2 --- Signal enhancement --- p.50 / Chapter 4.4 --- Conclusions --- p.52 / Chapter CHAPTER FIVE --- ANALYSIS OF HIGH MASS OLIGONUCLEOTIDES --- p.53 / Chapter 5.1 --- Introduction --- p.53 / Chapter 5.2 --- Experimental --- p.53 / Chapter 5.3 --- Results and Discussion --- p.54 / Chapter 5.4 --- Conclusions --- p.67 / Chapter CHAPTER SIX --- CONCLUSIONS AND FURTHER WORK --- p.68 / Chapter 6.1 --- Conclusions --- p.68 / Chapter 6.2 --- Further work --- p.70 / ACKNOWLEDGMENT --- p.A1 / REFERENCES --- p.R1 - R5

L'héparine (Hp) est un polysaccharide sulfaté appartenant à la famille des glycosaminoglycanes (GAGs), et est constitué d'unités de répétition disaccharidiques composées d’un acide hexauronique lié par une liaison α1→4 à un résidu hexosamine. La sulfatation de ce polysaccharide peut avoir lieu sur les positions 6-O ou N du glucosamine, mais également sur la position 2-O de l'acide hexauronique. En général, les GAGs sont O-liés aux chaînes latérales des protéoglycanes, et sont associés à un nombre important d'activités physiologiques, généralement reliées à leur interaction avec diverses protéines. Dans certains cas, cette interaction peut-être influencée par la liaison à ces complexes Hp/protéine d'ions métalliques naturels. Ceux-ci influencent l'affinité, la spécificité et la stabilité de ces complexes. En dépit de sa pertinence, le mécanisme par lequel un cation métallique module l'activité de l'héparine au sein des complexes Hp-protéine, reste largement méconnu.Un éventail de stratégies et d'outils ont été développés afin de faciliter la détermination des structures primaires des biomolécules par spectrométrie de masse en tandem (MS/MS). En effet, la caractérisation structurale de l'héparine sulfatée et de ses complexes métalliques a été soutenue par le développement de techniques de spectrométrie de masse. Dans certains cas, il a été observé que lors de l'activation par dissociation induite par collision (CID), certains de ces isomères d'héparine partageaient à peu près les mêmes schémas de fragmentation, compliquant de ce fait le processus d'identification de ces composés. Néanmoins, des études réalisées au LAMBE ont montré que la réactivité en phase gazeuse des ions métalliques pouvait aider à la différenciation d'isomères saccharidiques. Ces études peuvent être utiles non seulement du point de vue purement analytique, mais également parce que le comportement différent des isomères envers un métal donnée conduit à informations sur le processus d'interaction Hp/Métal mis en jeu. Cela peut s’avérer important pour interpréter les mécanismes biologiques mentionnées auparavant.Dugourd et al ont récemment rapporté les spectres optiques et les motifs de photodissociation de différents oligosaccharides sous irradiation UV. En terme de chemins de fragmentation, il a été observé que les spectres de photodissociation Ultraviolet (UVPD) apparaissaient être plus informatifs que la CID en raison de clivages à travers les cycles supplémentaires, qui fournissent une information sur la position du groupe sulfate. Le spectre optique des disaccharides sulfatés est caractérisé par une bande large et intense centrée vers 240 nm. Suite à ces résultats, nous nous sommes intéressés au couplage de la spectroscopie optique et des calculs théoriques pour les disaccharides d'héparine, et avons employé la spectroscopie UVPD afin d’obtenir des informations complémentaires sur les interactions de ces sucres avec les métaux.Comme décrit auparavant, les processus CID représentent un outil très précieux pour la caractérisation structurale des biomolécules. Motivés par des travaux antérieurs publiés par W. Hase et K. Song, nous avons collaboré avec les groupe de R. Spezia et T. Riera afin de parvenir à une meilleure compréhension du processus MS/MS des sucres et des peptides protonés. Les mécanismes CID de modèles simples, N-Formylalanylamide (HCO-Ala-NH2) et Galactose-6-Sulfate, ont été étudiés par des simulations de dynamique moléculaire QM+MM et des expériences MS/MS. Les objectifs de cette thèse étaient les suivants: i) explorer la possibilité d'utiliser le calcium métallique à des fins analytiques ii) fournir de nouvelles données sur la nature de l’interaction Hp/Ca2+ en utilisant une stratégie multi-approches combinant plusieurs techniques expérimentales et de calculs quantiques iii) étudier le processus CID de différents systèmes par des simulations de dynamique moléculaire. / Heparin (Hp) is a sulfated polysaccharide composed of repeating dissacharide units of hexauronic acid linked (α1→4) to an hexosamine residue that belongs to the family of glycosaminoglycans (GAGs). Sulfation can occur at the 6-O and/or N-positions of the gluscosamine, as well as the 2-O position of the hexauronic acid. GAGs usually exist as the O-linked side-chains of proteoglycans, associated with numerous important physiological activities, generally related to their interaction with diverse proteins. In some cases, this interaction can be influenced by the binding of natural metal ions to these Hp/protein complexes. Their role is usually pertained to the affinity, specificity and stability of these complexes. Despite its relevance, the mechanism by which the cation modulates heparin activity in Hp-protein complexes is largely unknown. A range of strategies and tools has been developed to facilitate the determination of primary structures of analyte molecules of interest via tandem mass spectrometry (MS/MS). In fact, structural characterization of heparin sulfated and its metal complexes has been sustained by the development of mass spectrometry techniques. In some cases, it was observed that upon collision-induced dissociation (CID) activation, some of these heparin-like isomers share nearly the same fragmentation patterns, turning the identification process into a complicated step. Nevertheless, a few years ago, our group showed that the gas-phase reactivity of metal ions can shed light into differentiating isomeric saccharides. These studies can be useful for two reasons: just for purely analytical purposes and also because the different behavior of the isomers towards the metal gives information about the Hp/Metal interaction. This might be important to explain the biological considerations mentioned before. Moreover, Dugourd et al recently reported the optical spectra and photodissociation patterns of different Hp oligosaccharides under UV irradiation. In terms of fragmentation pathways, it was observed that Ultraviolet photodissociation (UVPD) spectra appear to be more informative than CID due to additional cross-ring cleavages that provide information about the sulfate group location. Remarkably, the optical spectrum is characterized by an intense broad band centered at 240 nm for sulfated disaccharides. Following these findings, we became interested in coupling optical spectroscopy and theoretical calculations in heparin disaccharides and developing an alternative strategy to characterize these metal interactions. As described before, CID processes are commonly used in several fields and represent a very valuable tool in protein or carbohydrate characterization. Motivated by previous work published by W. Hase and K. Song, we collaborated with R.Spezia and T. Riera’s group in order to achieve a better understanding of the MS/MS process of protonated peptides and sugars. CID mechanisms of simple models, N-Formylalanylamide (HCO-Ala-NH2) and Galactose-6-Sulfate, were studied by QM+MM chemical dynamics simulations and MS/MS experiments.

This dissertation outlines the study and development of a Solid-state Impact-ionization Multiplier (SIM). The SIM is a stand-alone current amplifier designed with optical detection systems in mind. The SIM amplifies signals utilizing impact ionization as a source of gain. The SIM is fabricated on silicon in order to take advantage of its favorable impact ionization coefficients. Utilizing silicon in impact ionization based gain devices makes low noise and high gains attainable. Because it is a stand-alone device, it can be wired to an arbitrary current source making it capable of receiving an input from photodiodes of any material. This makes it possible to amplify a signal from a photodiode that has been optimized for a given wavelength. In this way, the SIM attempts to separate the absorption and multiplication portions in modern day optical detection/amplification devices such as in Avalanche Photodiodes (APDs). This flexibility allows it to be utilized in many different systems. The SIM has gone through several iterations in the last few years. Each change has been with the purpose of increasing gain, frequency response or yield. The progression of the device has come at the hand of much thought, theory, simulation, fabrication, and testing. One of the challenges encountered in its development has been gain controllability due to poor carrier confinement and premature breakdown. Increased gain control was developed through simulation and fabrication of a confining oxide layer. Yield and difficulties in consistent fabrication were also addressed by altering the input metallization and doping processes. The frequency response of the device has been the largest challenge in device development. Issues such as space charge, floating node voltage, edge effects and low signal amplification have caused limitations. Successes and attempts at overcoming these, and other, challenges is the basis of this dissertation of work.