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Dissertations / Theses on the topic 'Semiconductors; Gallium Arsenide'

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Published: 4 June 2021

Last updated: 1 February 2022

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1

Joyce, Timothy Bruce Frank. "The growth of gallium arsenide and gallium arsenide by chemical beam epitaxy." Thesis, University of Liverpool, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.240620.

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2

Muensit, Supasarote. "Piezoelectric coefficients of gallium arsenide, gallium nitride and aluminium nitride." Phd thesis, Australia : Macquarie University, 1999. http://hdl.handle.net/1959.14/36187.

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"1998"--T.p.
Thesis (PhD)--Macquarie University, School of Mathematics, Physics, Computing and Electronics, 1999.
Includes bibliographical references.
Introduction -- A Michelson interferometer for measurement of piezoelectric coefficients -- The piezoelectric coefficient of gallium arsenide -- Extensional piezoelectric coefficients of gallium nitrides and aluminium nitride -- Shear piezoelectric coefficients of gallium nitride and aluminium nitride -- Electrostriction in gallium nitride, aluminium nitride and gallium arsenide -- Summary and prognosis.
The present work represents the first use of the interferometric technique for determining the magnitude and sign of the piezoelectric coefficients of III-V compound semiconductors, in particular gallium arsenide (GaAs), gallium nitride (GaN), and aluminium nitride (AIN). The interferometer arrangement used in the present work was a Michelson interferometer, with the capability of achieving a resolution of 10⁻¹³ m. -- The samples used were of two types. The first were commercial wafers, with single crystal orientation. Both GaAs and GaN were obtained in this form. The second type of sample was polycrystalline thin films, grown in the semiconductor research laboratories at Macquarie University. GaN and AIN samples of this type were obtained. -- The d₁₄ coefficient of GaAs was measured by first measuring the d₃₃ value of a [111] oriented sample. This was then transformed to give the d₁₄ coefficient of the usual [001] oriented crystal. The value obtained for d₁₄ was (-2.7 ± 0.1) pmV⁻¹. This compares well with the most recent reported measurements of -2.69 pmV⁻¹. The significance of the measurement is that this represents the first time this coefficient has been measured using the inverse piezoelectric effect. -- For AIN and GaN samples, the present work also represents the first time their piezoelectric coefficients have been measured by interferometry. For GaN, this work presents the first reported measurements of the piezoelectric coefficients, and some of these results have recently been published by the (Muensit and Guy, 1998). The d₃₃ and d₃₁ coefficients for GaN were found to be (3.4 ± 0.1) pmV⁻¹ and (-1.7 ± 0.1) pmV⁻¹ respectively. Since these values were measured on a single crystal wafer and have been corrected for substrate clamping, the values should be a good measure of the true piezoelectric coefficients for bulk GaN. -- For AIN, the d₃₃ and d₃₁ coefficients were found to be (5.1 ± 0.2) pmV⁻¹, and (-2.6 ± 0.1) pmV⁻¹ respectively. Since these figures are measured on a polycrystalline sample it is quite probable that the values for bulk AIN would be somewhat higher.
The piezoelectric measurements indicate that the positive c axis in the nitride films points away from the substrate. The piezoelectric measurements provide a simple means for identifying the positive c axis direction. -- The interferometric technique has also been used to measure the shear piezoelectric coefficient d₁₅ for AIN and GaN. This work represents the first application of this technique to measure this particular coefficient. The d₁₅ coefficients for AIN and GaN were found to be (-3.6 ± 0.1) pmV⁻¹ and (-3.1 ± 0.1) pmV⁻¹ respectively. The value for AIN agrees reasonably well with the only reported value available in the literature of -4.08 pmV⁻¹. The value of this coefficient for GaN has not been measured. -- Some initial investigations into the phenomenon of electrostriction in the compound semiconductors were also performed. It appears that these materials have both a piezoelectric response and a significant electrostrictive response. For the polycrystalline GaN and AIN, the values of the M₃₃ coefficients are of the order of 10⁻¹⁸ m²V⁻². The commercial single crystal GaN and GaAs wafers display an asymmetric response which cannot be explained.
Mode of access: World Wide Web.
Various pagings ill

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3

Hendricks, Douglas Ray 1958. "REACTIVE ION ETCHING OF GALLIUM-ARSENIDE AND ALUMINUM-GALLIUM - ARSENIDE USING BORON TRICHLORIDE AND CHLORINE." Thesis, The University of Arizona, 1987. http://hdl.handle.net/10150/276394.

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4

Peng, Harry W. "The effects of stress on gallium arsenide device characteristics." Thesis, University of British Columbia, 1988. http://hdl.handle.net/2429/28584.

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For VLSI applications, it is essential to have consistent device characteristics for devices fabricated on different fabrication runs, on different wafers, and especially across a single wafer. MESFETs fabricated on GaAs have been found to have an orientation dependence in their threshold voltage and other characteristics. For MESFETs with gate length less than 2 μm, changing the device orientation can so significantly alter the device characteristics that it must be considered during the transistor design stage. The causes for the orientation dependence in the device characteristics have been suggested to be the piezoelectric property of GaAs and stress in the substrate. Stress produced by the encapsulating dielectric film generates a polarization charge density in the substrate. If the magnitude of the polarization charge density is large enough to alter the channel doping profile, then the device characteristics are changed. In this thesis, the effects of stress on GaAs MESFET device characteristics were studied by modelling and experimental works. In the modelling part, polarization charge densities under the gate of an encapsulated MESFET were calculated by using the so called distributed force model and the edge concentrated model. The distributed force model is a much better model because it describes more realistically the stress distribution in the film and in the substrate. It should provide a much more accurate calculation of the induced polarization charge density. The results show that the polarizarition charge densities calculated by the two models have similar distribution pattern, but the magnitudes are very different. With an identical set of conditions, a much larger polarization charge density is predicted by the edge concentrated model. In addition, the distributed force model distinguishes different films by a "hardness" value, based on their elastic property, whereas the edge concentrated model does not. A film with a larger "hardness" value is predicted to generate a larger polarization charge density. Two types of film were considered, SiO₂ and Si₃N₄. Using bulk film characteristics, the calculations showed that Si0₂ film is "harder" than Si₃N₄ film. If an equal built-in stress value is assumed, then a larger polarization charge density is predicted for Si0₂ than for Si₃N₄ encapsulated substrates. In the experimental part, stress was applied to test devices by bending strips of GaAs wafers in a cantilever configuration. MESFETs tested were oriented in the [011] or the [011̅] direction. Both static stress and time-varying stress were applied. In the statics stress experiment, the changes in the barrier height and the C-V profile were measured. It was found that, with equal stress applied, Schottky barriers with a larger ideality factor showed a larger change in the barrier height. In the time-varying stress experiment, attempts were made to measure the effect of the polarization charge density on device characteristics by measuring changes in the drain-source current.
Applied Science, Faculty of
Electrical and Computer Engineering, Department of
Graduate

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5

Feng, Guofu. "Optical studies of ion-bombarded gallium arsenide." Diss., Virginia Polytechnic Institute and State University, 1989. http://hdl.handle.net/10919/54357.

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The present work studies the disorder in ion-implanted and ion-etched GaAs semiconductors. The primary targets in this study consist of two types of systems:45-keV Be⁺-implanted GaAs and low-energy Ar⁺-etched GaAs. Electronic and lattice structural disorder in these systems are investigated by means of optical reflectivity measurements and Raman-scattering techniques. Visible-ultraviolet reflectivity measurements have identified finite-size effects on the interband electronic excitations in microcrystalline GaAs (μ-GaAs), which is known from previous work to exist in Be⁺-implanted disordered GaAs. The optical properties of μ-GaAs differ appreciably from those of the bulk crystal, the difference increasing with L⁻¹, the inverse of the characteristic size of the microcrystals. The linewidths of the prominent interband features E₁, E₁+∆₁, and E₂ increase linearly and rapidly with inverse microcrystal size: Γ_μ = Γ₀ + AL⁻¹, where Γ₀ (Γ_μ) is the linewidth in the bulk crystal (μ-GaAs), and A is a constant. A simple theory is proposed which semi-quantitatively accounts for the observed size effects. Small microcrystal size implies a short time for an excited carrier to reach, and to be scattered by, the microcrystal boundary, thus limiting the excited-state lifetime and broadening the excited-state energy. An alternative uncertainty-principle argument is also given in terms of the confinement-induced k-space broadening of electron states. The near-surface structural disorder in Ar⁺-etched GaAs has been investigated using a combination of Raman scattering and optical reflectivity measurements. The longitudinal optical (LO) Raman mode in the ion-damaged medium preserves its crystalline lineshape, indicating that the crystalline long-range order is retained in the disordered structure. The structural damage is depth-profiled with LO Raman intensity measurements together with wet chemical etching. A graded damage model proposed in the work well explains the observed LO intensity in the ion-damaged, chemical-etched GaAs. The reflectivity measurements qualitatively support the Raman scattering findings. In addition, the reflectivity spectrum exhibits a red-shift of the peaks associated with the interband electronic transitions. Such a peak shift is likely to arise from the electron-defect interaction in the disordered surface medium.
Ph. D.

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6

Jeffery, Arvi Denbigh 1960. "MEASUREMENT AND MODELING OF THE NONLINEAR ABSORPTION AND REFRACTIVE INDEX OF BULK GALLIUM-ARSENIDE AND GALLIUM-ARSENIDE/ALUMINUM-GALLIUM - ARSENIDE MULTIPLE-QUANTUM-WELLS." Thesis, The University of Arizona, 1987. http://hdl.handle.net/10150/276435.

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7

Rutherford, William C. "Gallium arsenide integrated circuit modeling, layout and fabrication." Thesis, University of British Columbia, 1987. http://hdl.handle.net/2429/26733.

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The object of the work described in this thesis was to develop GaAs integrated circuit modeling techniques based on a modified version of SPICE 2, then layout, fabricate, model and test ion implanted GaAs MESFET integrated sample and hold circuits. A large signal GaAs MESFET model was used in SPICE to evaluate the relative performance of inverted common drain logic (ICDL) digital integrated circuits compared to other circuit configurations. The integrated sample and hold subsequently referred to as an integrated sampling amplifier block(ISAB), uses a MESFET switch with either one or two guard gates to suppress strobe feedthrough. Performance guidelines suggested by the project sponsor indicate an optimal switch sampling pulse width capability of 25 ps with 5 ps rise and fall time. Guard gates are included in the switch layout to evaluate pulse feedthrough minimization. The project sponsor suggested -20 dB pulse feedthrough isolation and minimum sampling switch off isolation of -20 dB at 10 GHz as project guidelines. Simulations indicate that a 0.5 µm gate length process approaches the suggested performance guidelines. A mask layout was designed and modeled including both selective implant and refractory self aligned gate processes. The refractory self aligned gate process plasma etched t-gate structure produces a sub 0.5 µm gate length.
Applied Science, Faculty of
Electrical and Computer Engineering, Department of
Graduate

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8

MacPherson, Glyn. "Distribution and control of misfit dislocations in indium gallium arsenide layers grown on gallium arsenide substrates." Thesis, University of Liverpool, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.318239.

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9

Goringe, Chris. "Computational modelling of reactions on gallium arsenide surfaces." Thesis, University of Oxford, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.296894.

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10

Bates, Richard L. "Gallium arsenide radiation detectors for the ATLAS experiment." Thesis, University of Glasgow, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.360170.

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11

Siochi, Ramon Alfredo Carvalho. "Optical characterization of processed gallium arsenide." Diss., Virginia Tech, 1990. http://hdl.handle.net/10919/39851.

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12

Liu, Jia. "Optical spectroscopic study of GaAs with dilute nitrogen doping /." View Abstract or Full-Text, 2002. http://library.ust.hk/cgi/db/thesis.pl?PHYS%202002%20LIU.

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13

Khatwani, Rani. "Electrical characterization of epitaxial layers of gallium arsenide /." Full text open access at:, 1988. http://content.ohsu.edu/u?/etd,180.

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14

Hui, David C. W. "Characterization of semi-insulating liquid encapsulated Czochralski gallium arsenide." Thesis, University of British Columbia, 1989. http://hdl.handle.net/2429/30648.

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This thesis consists of a study of several qualification techniques for SI LEC GaAs and the application of these techniques to various ingots. For use on the starting material before any doping procedures, the technique of studying the semi-insulating properties by monitoring the activation energy of dark resistivity with temperature was investigated. Experiments were performed on both ring dot as well as cloverleaf samples. Different activation energies for the dark resistivity were observed for temperatures above and below 290 K. Also, ingots with different background impurity concentrations were tested. Another technique applicable to the undoped starting material is Optical Transient Current Spectroscopy (OTCS). The occurrence of 'negative' peaks was simulated using a depletion layer model. The results showed that under certain conditions a recombination centre can produce a positive peak, a negative peak, or both a positive and a negative peak. Further analysis of the negative peaks led to the formulation of a field enhanced injection model to explain their occurrence. More than one negative peak was observed experimentally. In addition, the effect of different electrode structures on OTCS experiments was investigated. The effect of polarity on negative peaks was studied using ring dot structures and was found to agree with the proposed model. Some peculiar anomalies which were observed in investigating OTCS led to the discovery of a photocurrent memory effect with decay time constants of the order of minutes at a temperature of 266 K. This memory effect was found to be associated with surface modifications. The effects of surface passivation with Na₂S were investigated. The method of normalizing the OTCS peak height with photocurrent was investigated. A microscopic spatial analysis tool, scanning OTCS, with a spot size of about 2 µm was developed in order to probe the spatial variation of deep levels and compare with that of dislocations or other defects. An experiment on an abraded surface was performed using the scanning OTCS and showed that the negative peak does indeed correlate with mechanical damage. Wafer performance during implantation doping is an important qualification test. Comparisons between standard furnace annealing and rapid thermal annealing were performed. A comparison of the estimated percentage activation using C(V) measurements with that from Hall measurements, with and without a correction for the surface depleted region, was performed. The C(V) analysis technique, used in the industry to obtain doping profiles of implanted wafers, was studied. The effect of using serial and parallel measurement modes was investigated. Simulations of C(V) measurements on implanted devices by solving the Poisson-Boltzmann equation for the charge distribution under different biases were performed. The limitation of the C(V) profiling technique in detecting sharp dopant profiles was investigated. A system for quick analysis of the percentage of activation using a mercury probe was designed. The effect of serial and parallel analysis of the impedance measured by the mercury probe on the estimated dopant profile was investigated. The effect of different electrode structures (Schottky to Schottky as compared to Schottky to Ohmic) on estimated doping profiles was studied. The mobility profile as a tool for qualification was investigated. The effect of surface states on mobility was studied. A crucial factor in wafer qualification is the uniformity of transistor characteristics across the wafer. In order to test this on a wafer, thousands of transistors have to be measured. A technique of perforating measurements automatically with consistency is needed. An automatic probing station for measuring large arrays of transistors was engineered. Tests on arrays of transistors were performed to investigate the effect of different fabrication processes, in particular the amount of surface etch, on the uniformity of threshold voltage.
Applied Science, Faculty of
Electrical and Computer Engineering, Department of
Graduate

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15

Yun, Henry K. "Growth and characterization of GaAsN compound semiconductors /." Thesis, Connect to this title online; UW restricted, 2001. http://hdl.handle.net/1773/10614.

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16

Westwater, Simon Phillip. "Heavily carbon doped gallium arsenide grown by chemical beam epitaxy." Thesis, University of Liverpool, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.263763.

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17

Janse, van Vuuren Arno. "Radiation damage in GaAs and SiC." Thesis, Nelson Mandela Metropolitan University, 2011. http://hdl.handle.net/10948/1477.

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In this dissertation the microstructure and hardness of phosphorous implanted SiC and neutron irradiated SiC and GaAs have been investigated. SiC is important due to its application as a barrier coating layer in coated particle fuel used in high temperature gas cooled reactors. The characterisation of neutron irradiated GaAs has been included in this study in order to compare the radiation damage produced by protons and neutrons since proton bombardment of SiC could in principle be used for out-of-reactor simulations of the neutron irradiation damage created in SiC during reactor operation. The following SiC and GaAs compounds were investigated: As-implanted and annealed single crystal 6H-SiC wafers and polycrystalline 3C-SiC bulk material implanted with phosphorous ions. As-irradiated and annealed polycrystalline 3C-SiC bulk material irradiated with fast neutrons. As-irradiated and annealed single crystal GaAs wafers irradiated with fast neutrons. The main techniques used for the analyses were transmission electron microscopy (TEM) and nano-indentation hardness testing. The following results were obtained for the investigation of implanted and irradiated SiC and GaAs: Phosphorous Implanted 6H-SiC and 3C-SiC The depth of the P+ ion damage was found to be in good agreement with predictions by TRIM 2010. Micro-diffraction of the damage region in P+ implanted 6H-SiC (dose 5×1016 ions/cm2) indicates that amorphization occurred and that recrystallisation of this layer occurred during annealing at 1200°C. TEM analysis revealed that the layer recrystallised in the 3C phase of SiC and twin defects also formed within the layer. Micro-diffraction of the damage region in P+ implanted 3C-SiC (dose 1×1015 ions/cm2) indicates that amorphization also occurred for this sample and that recrystallisation of this layer occurred during annealing at 800°C. Nano-hardness testing of the P+ implanted 6H-SiC indicated that the hardness of the implanted SiC was initially much lower than unimplanted SiC due to the formation of an amorphous layer during ion implantation. After annealing the implanted SiC at 800°C and 1200°C, the hardness increased due to re-crystallisation and point defect hardening. Neutron Irradiated 3C-SiC TEM investigations of neutron irradiated 3C-SiC revealed the presence dark spot defects for SiC samples irradiated to a dose of 5.9×1021 n/cm2 and 9.6×1021 n/cm2. Neutron Irradiated GaAs TEM investigation revealed a high density of dislocation loops in the unannealed neutron irradiated GaAs. The loop diameters increased after post-irradiation annealing in the range 600 to 800 °C. The dislocation loops were found to be of interstitial type lying on the {110} cleavage planes of GaAs. This finding is in agreement with earlier studies on 300 keV proton bombarded and 1 MeV electron irradiated GaAs where interstitial loops on {110} planes became visible after annealing at temperatures exceeding 500 °C. The small dislocation loops on the {110} planes of the neutron irradiated GaAs transformed to large loops and dislocations after annealing at 1000 °C.

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18

Kelkar, Kapil S. "Semiconductor modeling for multi-layer, high field photo switch using sub-bandgap photons /." free to MU campus, to others for purchase, 2004. http://wwwlib.umi.com/cr/mo/fullcit?p1421147.

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19

Modi, Nihar Triplett Gregory Edward. "Thermal management in GaAs/AlGaAs laser diode structures." Diss., Columbia, Mo. : University of Missouri--Columbia, 2007. http://hdl.handle.net/10355/6262.

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Title from PDF of title page (University of Missouri--Columbia, viewed on Feb. 16, 2010). The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Thesis supervisor: Dr. Gregory Triplett. Includes bibliographical references.

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20

Baba-Ali, N. "Diffusion of sulphur and silicon in aluminium gallium arsenide." Thesis, University of Nottingham, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.334989.

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21

Rosner, Mitchell Harris. "ARSENIC METABOLITE ANALYSIS AFTER GALLIUM-ARSENIDE AND ARSENIC OXIDE ADMINISTRATION (DISTRIBUTION, EXCRETION, SOLUBILITY, HAMSTER)." Thesis, The University of Arizona, 1985. http://hdl.handle.net/10150/275409.

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22

Schucan, Gian-Mattia. "Generation of squeezed light in semiconductors." Thesis, University of Oxford, 1999. http://ora.ox.ac.uk/objects/uuid:417b1d31-8d25-42db-b707-32bd460b4183.

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We present experimental studies based on all three methods by which the generation of squeezed light in semiconductors has thus far been demonstrated experimentally: Fourwave mixing, multi-photon absorption and direct generation at the source. Four-wave mixing was used to generate femtosecond-pulsed quadrature squeezed light by cross-phase modulation in single-crystal hexagonal CdSe at wavelengths between 1.42 and 1.55 μm. We measured 0.4 dB squeezing (1.1 dB is inferred at the crystal) using 100 fs pulses. The wavelength and the intensity dependence, as well as variations in the local oscillator configuration were investigated. At higher intensities squeezing was shown to deteriorate owing to competing nonlinear processes. We also characterised the nonlinear optical properties of CdSe in this wavelengths range using an interferometric autocorrelator. In addition, we studied the feasibility of extending this technique to AlGaAs waveguides. The key problems are addressed and solutions are proposed. In a different experiment we used an AlGaAs waveguide to demonstrate for the first time photon-number squeezing by multi-photon absorption. By tuning the pump energy through the half bandgap energy we could effectively select two- or three-photon absorption as the dominant mechanism. Squeezing by these two mechanisms could be clearly distinguished and was found to be in good agreement with longstanding theoretical predictions. We also established the generality of the effect, by demonstrating the same mechanism in organic semiconductors, where it led to the first ever observation of squeezed light in an organic material. Finally, we present our measurements of photon-number squeezing in high-efficiency double heterojunction AlGaAs light-emitting diodes. We measured squeezing of up to 2.0 dB. In addition, we observed quantum noise correlations when several of these devices were connected in series.

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23

Huang, Ying. "Electronic states and optical properties of GaAs/AIGaAs and GaInP/AlGaInP quantum wells." Thesis, Click to view the E-thesis via HKUTO, 2004. http://sunzi.lib.hku.hk/hkuto/record/B31479820.

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24

Rosner, Mitchell Harris. "Elucidation of the mechanism of gallium-arsenide induced pulmonary toxicity." Diss., The University of Arizona, 1989. http://hdl.handle.net/10150/184627.

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Gallium arsenide (GaAs) elicited a pulmonary inflammatory response in a dose dependent manner following a single exposure. A significant influx of leukocytes (polymorphonuclear cells) was observed 24 hours after intratracheal instillation of rats and hamsters. This led to an increase in the lung/body weight ratios. An increase in pulmonary DNA and total protein accompanied these observations. Histology confirmed the presence of increased numbers of pulmonary alveolar macrophages (PAM) even 1 week after exposure to GaAs. The instillation of GaAs also appeared to produce an oxidative stress in the lung only when the animals were given the 100 mg/kg dose and not the 10 mg/kg dose. Increased glutathione peroxidase and nonprotein sulfhydryls and depletion of ascorbic acid were evidence for the oxidative stress produced in the lung. These effects were dependent on the influx of phagocytic leukocytes. Analysis of the bronchoalveolar lavage fluid (BALF) also confirmed the involvement of phagocytic leukocytes in the progression of the lesions. Acid phosphatase activities increased significantly above the control levels 24 hours after exposure. The elevation of soluble protein and alkaline phosphatase indicated that the type I pneumocyte-capillary endothelial cell interface was compromised and the type II cells were damaged, respectively. The histological evaluations confirmed this phenomenon. Alveolar wall thickening was quite characteristic of the GaAs exposure. GaAs stimulated PAM to produce the active oxygen species, superoxide anion (O₂⁻) and H₂O₂, following in vitro and in vivo exposure. The dissolution of GaAs did not produce and O₂⁻ or H₂O₂ without the presence of cells. The cytotoxicity of GaAs was comparable to other compounds that elicit collagen deposition, As₂O₃ and silica. The semiconductor properties and potential dissolution products of GaAs may both contribute to its toxicity to PAM. The differences seen in the pulmonary lesions of silica (fibrosis) and GaAs (resorption of deposited collagen) treated animals may be due to the persistence of the particles. GaAs may be cleared by dissolution and silica cannot.

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25

Galloway, Simon A. "The electrical properties of dislocations in GaAs." Thesis, University of Oxford, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.386991.

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26

Dai, Junfeng, and 戴俊峰. "Spin photocurrent induced by interband transition." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2010. http://hdl.handle.net/10722/210326.

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27

Bousbahi, K. "Investigations of some defects in GaAs and some transport properties of GaAs/(AlGa)As heterojunctions." Thesis, University of Nottingham, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.356075.

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28

Tayrani, R. "GaAs monolithic control devices and circuits." Thesis, University of Kent, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.376796.

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29

Murape, Davison Munyaradzi. "On the electrical characterisation of bulk and epitaxial n-type Te doped GaSb." Thesis, Nelson Mandela Metropolitan University, 2014. http://hdl.handle.net/10948/d1020763.

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Since the development of the transistor in the Bell Telephone Laboratories in 1948 [78], the semiconductor industry has transformed the world we live in. It is difficult to picture a world without the modern day cutting edge technology. Imagine performing every day functions without “trivial” devices such as computers, cell phones or microwave ovens. The ability to tailor the band gaps of various binary, ternary and quaternary semiconductor systems has opened up a whole new spectrum of potential purpose designed devices [27]. This thesis focuses on the electronic properties of gallium (III) antimonide (V). The antimonides, in general, have the smallest band gap and highest electron mobility of the III-V compound semiconductors and are well suited for long wavelength emission and detection as well as high frequency switching device applications. Furthermore, III-V ternaries and quaternaries, such as (AlGaIn)(AsSb), lattice matched to gallium antimonide (GaSb) are considered serious competitors for HgCdTe and PbSe in long-wavelength infrared (LWIR) and very long-wavelength infrared (VLWIR) technology [4, 10, 11]. Epitaxial material systems based on GaSb are suitable for a wide range of applications such as missile and surveillance systems and a host of other military and civil applications. In addition, an assortment of devices on InAs, GaSb, and AlSb, including resonant tunnelling devices, infrared detectors and mid-infrared semiconductor lasers have been demonstrated [14, 15]. Furthermore, antimonide based devices could potentially reduce optical fibre power loss by a few orders of magnitude, as their implementation can lead to use of non-silica based optical fibres that minimise Raleigh scatter related power loss [8]. GaSb related technology faces a number of challenges. A significant amount of effort is required to exploit the potential it offers. GaSb oxidises readily in the ambient, resulting in the formation of a native oxide layer as well as deposits of elemental antimony (Sb) at the oxide/substrate interface therefore it has poor surface electronic properties resulting from high surface state densities[4, 17, 18]. As grown GaSb is characterised by a high density of surface states of which many are classified as non-radiative (Auger) recombination centres. The elemental Sb layer constitutes an unwanted conduction path parallel to the active surface region [17]. The potential that GaSb and GaSb-based strained layer superlattices offer as successors to the current generation of LWIR and VLWIR optoelectronic materials has therefore been largely impeded [4]. Furthermore, processing steps in device fabrication leads to an unintentionally damaged GaSb surface exacerbating the situation. Any efforts to engineer devices of superior quality on GaSb have to address these and more material specific problems [19]. This study attempts to contribute towards an improved understanding of the structural and electrical properties of the near surface region of Te-doped bulk (100) and MOVPE grown epitaxial Te doped n- GaSb. The main focus of this study is to develop means to de-oxidise and stabilize the highly reactive GaSb surface and to develop diode structures to demonstrate the improved interface characteristics and use related current–voltage (I-V) measurements to quantify the surface state density before and after treatment. These devices were also used to probe the near surface region for electrically active deep level defects that often act as non-radiative recombination centers. Au, Pd and Al were used as metals to establish a metal semiconductor barrier and subsequent depletion region. Sulphur based chemicals, ([(NH4)2S / (NH4)2SO4] + S), not previously reported for the treatment of (100) n-GaSb surfaces, and the commonly used passivants Na2S:9H2O and (NH4)2S were compared by assessing the electrical and structural properties both before and after treatment. The effect of treatment on the electrical response of the material was determined using current-voltage, capacitance-voltage (C-V) and deep level transient spectroscopy (DLTS) measurements, while the surface morphology and composition were studied by SEM, AES and XPS.

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30

Woodworth, Sean C. Cassidy Daniel Thomas. "Design, theory, and applications of broad gain profile indium gallium arsenide phosphide diode lasers /." *McMaster only, 2005.

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31

Og̃uzman, İsmail Hakki. "Monte Carlo study of hole transport in bulk silicon, gallium arsenide, gallium nitride and relate device structures." Diss., Georgia Institute of Technology, 1996. http://hdl.handle.net/1853/16712.

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32

Puttock, Mark Stephen. "The study of surface damage of gallium arsenide induced by reactive ion etching." Thesis, Cardiff University, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.309647.

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33

Ma, Shun-kit Martin. "The two gallium vacancy-related defects in undoped gallium antimonide." Click to view the E-thesis via HKUTO, 2004. http://sunzi.lib.hku.hk/hkuto/record/B31319658.

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34

Rinzan, Mohamed Buhary. "Threshold extension of gallium arsenide/aluminum gallium arsenide terahetrz detectors and switching in heterostructures." unrestricted, 2006. http://etd.gsu.edu/theses/available/etd-10102006-204618/.

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Thesis (Ph. D.)--Georgia State University, 2006.
Title from title screen. Unil Perera, committee chair; Donald Edwards, Gennady Cymbaluyk, Mark Stockman, Nikolaus Dietz, Paul Wiita, committee members. Electronic text (348, 24-32 p. : ill.) : digital, PDF file. Description based on contents viewed June 8, 2007. Includes bibliographical references (p. 24-30, second sequence).

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35

Wilkinson, Lucinda Clare. "Indium gallium arsenide multiple quantum well devices for optically interconnected smart pixels." Thesis, Heriot-Watt University, 1998. http://hdl.handle.net/10399/640.

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36

Hanson, Craig Demorest 1956. "Demonstration of capabilities of gallium arsenide etalons for practical optical logic." Thesis, The University of Arizona, 1989. http://hdl.handle.net/10150/277204.

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All-optical logic gates made from GaAs etalons were studied to see if they may be useful for optical computing. We have demonstrated that GaAs etalons may produce a change in output optical signal four times larger than the change in the input signal, and that the contrast of the output signal may be as high as 10 to 1. We have cascaded two GaAs etalons, i.e. the output change in the first causes the second one to switch. We have combined two signal beams and a biasing beam onto a GaAs etalon using polarized beams for a fan-in investigation, and have demonstrated that this setup may be used as an all-optical AND gate. We have also shown that GaAs etalons function well when interfaced to optical fibers by direct butt-coupling. Interconnections between all-optical gates by optical fibers, holographic optical elements, and conventional lenses are discussed.

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37

Filleul, Maria Louise. "An examination of the damage caused by the reactive ion etching of gallium arsenide." Thesis, University College London (University of London), 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.296102.

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38

Ma, Shun-kit Martin, and 馬信傑. "The two gallium vacancy-related defects in undoped gallium antimonide." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2004. http://hub.hku.hk/bib/B31319658.

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39

Wang, Yong. "Research on improvement of breakdown voltage of AlGaN/GaN HEMTs grown on Si(111) substrates by MOCVD /." View abstract or full-text, 2009. http://library.ust.hk/cgi/db/thesis.pl?ECED%202009%20WANGY.

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40

Michels, Joseph Gerard. "Optically detected cyclotron resonance of GaAs-based semiconductors." Thesis, University of Oxford, 1994. http://ora.ox.ac.uk/objects/uuid:20ffc752-d7e7-4631-803a-bfeb9b12dfc6.

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Cyclotron resonance has been measured in GaAs and related compounds through the use of a new experimental technique developed for the study of very pure semiconductors called optically detected cyclotron resonance (ODCR). ODCR differs from other forms of magnetospectroscopy in that the intensity of luminescence excited by a visible laser is monitored rather than the direct absorption of far-infrared radiation. The ODCR technique is initially used on an exceptionally pure sample of GaAs and resolves impurity transitions and central cell effects. An accurate measure of the electron effective mass including band nonparabolicity is made. The ODCR signal represents an interaction between the donor bound electron states and the donor bound exciton states. Standard cyclotron resonance measurements on high mobility GaAs/Ga₁-_xAl_xAs heterojunctions are performed with tilted magnetic fields. Resonant coupling between the Landau levels and electric subbands gives rise to a splitting of the cyclotron resonance lineshape which can be used to determine the subband energy spacings. This allows for a direct determination of the shape of the confinement potential which changes dramatically under different illumination conditions. A dilution refrigerator is modified in order to measure the cyclotron resonance (CR) to 100 mK of the low density, two dimensional electron system in a heterojunction. Anomalies in the CR spectrum are explained in terms of an interacting electron system composed of carriers in the two spin states of the lowest Landau level. Experimental results are presented in terms of a recent theory offered for cyclotron resonance. A series of undoped GaAs quantum wells is studied with ODCR. The conduction band mass was measured for different well widths. An offset is observed in the cyclotron resonance energy which is strongly dependent on the well width. ODCR is measured on In_0.05Ga_0.95As/GaAs superlattices using both the Faraday and Voigt magnetic field orientations. Cyclotron resonance in the Voigt geometry reveals a band structure in the growth direction. The impurity transition in the Voigt configuration shifts dramatically, moving from the bulk 1s-2p + to close to the bulk free electron field.

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41

Breevoort, Cornelius Marius. "A 9-bit, pipelined GaAs analog-digital converter." Diss., Georgia Institute of Technology, 1992. http://hdl.handle.net/1853/15036.

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42

凌志聰 and Chi-chung Francis Ling. "Positron beam studies of the metal-GaAs (110) interface." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1994. http://hub.hku.hk/bib/B31211689.

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43

雷美琪 and Mei-ki Pattie Lui. "Positron lifetime study of Zn-doped GaSb." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2001. http://hub.hku.hk/bib/B31226437.

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44

Lui, Mei-ki Pattie. "Positron lifetime study of Zn-doped GaSb /." Hong Kong : University of Hong Kong, 2001. http://sunzi.lib.hku.hk/hkuto/record.jsp?B24534328.

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45

Ling, Chi-chung Francis. "Positron beam studies of the metal-GaAs (110) interface /." [Hong Kong : University of Hong Kong], 1994. http://sunzi.lib.hku.hk/hkuto/record.jsp?B13781443.

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46

Booth, Ian. "Optical detection of paramagnetic and cyclotron resonance in semiconductors." Thesis, University of British Columbia, 1985. http://hdl.handle.net/2429/25566.

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Optical Detection of Magnetic Resonance (ODMR) has been used to observe both paramagnetic and diamagnetic resonance of photo-excited electrons and holes in GaP, ZnTe and AgBr. Paramagnetic resonance of conduction electrons in GaP has been studied and the microwave frequency and power dependence of the effect analysed. The maximum signal strength was observed to produce approximately 1% change in luminescence at 1.6 K. The g value deduced from the resonance was 2.000 ± 0.005. The resonance was homogeneously broadened giving the electron lifetime as approximately 4 nanoseconds. Paramagnetic resonance of electrons and holes has also been detected in AgBr. The background signals present in ODMR experiments have been investigated and are shown to be caused by diamagnetic or cyclotron resonance heating of photoexcited carriers. Measurements at microwave frequencies of 9.2 and 36.3 GHz have been made on GaP,ZnTe and AgBr, and cyclotron resonance of electrons and holes observed. The effective masses of light and heavy holes in GaP were found to be 0.154 ± 0.01 and 0.626 ± 0.06 respectively while the electron effective mass was 0.36 ± 0.10. The electron scattering time was shorter than that for holes by a factor of approximately three, most likely due to scattering by isoelectronic nitrogen impurities. Resonances were observed in ZnTe at effective mass values of 0.30 ± 0.20 and 0.76 ± 0.20 corresponding to electrons and heavy holes. In both GaP and ZnTe resonances due to electrons and holes appeared in different luminescence bands indicating the sensitivity of different recombination centres to heating of either carrier type. Cyclotron resonance of electrons and holes was also observed in AgBr and showed the effects of conduction and valence band non-parabolicity. A feature in the electron resonance indicated enhanced trapping of electrons with certain energies by emission of one or more LO phonons.
Science, Faculty of
Physics and Astronomy, Department of
Graduate

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47

LEE, YONG HEE. "ROOM-TEMPERATURE OPTICAL NONLINEARITIES IN GALLIUM-ARSENIDE AND FAST OPTICAL LOGIC GATES." Diss., The University of Arizona, 1986. http://hdl.handle.net/10150/183920.

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This dissertation studies the physics of room-temperature optical nonlinearities in GaAs and their application to the optical logic gates. The microscopic origins of the room-temperature optical nonlinearities in GaAs are investigated experimentally and theoretically. The data of nonlinear absorption measurement are analyzed in the framework of a semiconductor plasma theory in combination with excitation-dependent line broadening. The importance of the plasma screening of the continuum-state Coulomb enhancement and band filling are emphasized for GaAs at room temperature. Optical bistability and optical logic gating are direct consequences of the nonlinear refractive index changes in etalons. The nonlinear index changes are directly measured by a new technique of observing the Fabry-Perot transmission peak shift using the self-photoluminescence as a broad-band source. The validity of a Kramers-Kronig technique under quasi-steady state conditions is crosschecked by an independent measurement of Δn under identical pumping conditions. Thermal index changes are also directly measured to establish the criteria on the temperature stability condition that is needed for reliable operation of devices based on dispersive nonlinearities. Optical logic gates based on dispersive optical nonlinearities may be the critical components of an all-optical computer in the future. Five optical logic functions are demonstrated in a nonlinear GaAs/AlGaAs MQW etalon. Specially designed dielectric mirrors are used to observe low-energy (3-pJ) operation of optical logic gates. Parallel operation using as many as eight optical logic devices is achieved with Wollaston prisms. Toward practical devices, optical logic gating using diode lasers is demonstrated in a setup much smaller than the usual argon-laser pumped dye laser setup. The cycle time of optical logic devices is limited, not by the switch-on time, but by the switch-off time which depends on the carrier relaxation rather than the switch-on time. To reduce the carrier relaxation time windowless GaAs is employed to take advantage of the faster surface recombination of carriers at the GaAs/dielectric mirror interface compared to that at the GaAs/GaAlAs interface. The speed and effectiveness of the windowless GaAs are compared with those of the proton-bombarded GaAs as optical logic gates.

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48

Warren, Mial Evans. "Fabrication, experimental investigation and computer modeling of gallium-arsenide nonlinear optical devices." Diss., The University of Arizona, 1988. http://hdl.handle.net/10150/184330.

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Nonlinear-optical switching and logic devices based on GaAs nonlinear Fabry-Perot etalons have been investigated theoretically and experimentally. The theoretical modeling has been performed with the first realistic and easily computed theory of GaAs nonlinear optical properties near the band edge. Both steady-state and dynamic calculations have been performed for optical bistability with GaAs etalons. High-transmission operation is predicted for certain etalon detunings from the excitation wavelength. Various logic-gate functions have simulated with the model. An investigation of differential energy gain in transient, one-wavelength operation was performed. The conclusion is that useful differential gain is not achievable in transient, one-wavelength operation if the pulse width is less than about ten times the carrier lifetime in the material. Waveguide structures with single-mode transverse confinement were designed and optical bistability was predicted for long GaAs etalons similar to cleaved waveguides. GaAs nonlinear optical devices were fabricated in forms of interest for application to optical parallel processing and guided wave signal processing. The fabrication work included etalon arrays and waveguide devices fabricated by reactive ion etching. The photolithography and reactive ion etching processes used and developed are described. Preliminary work on ultra-small quantum-confinement structures is described. Optical experiments were performed on the devices fabricated. The etalon arrays demonstrated extremely fast relaxation times for GaAs etalon devices, and demonstrated the ability to control material parameters through the fabrication process, by increasing the surface recombination rate of charge carriers. Fast optical bistability at low powers was also demonstrated in the array devices. Strip-loaded waveguides with cleaved ends were operated as optical bistable devices with conclusive evidence that the mechanism was electronic in origin. Nonlinear phase shifts of greater than $2\pi$ were observed in some waveguides. Such large nonlinear phase shifts are of great interest for the development of other nonlinear-optical waveguide devices.

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49

Goss, Jonathan Paul. "A first principles study of defects in semiconductors." Thesis, University of Exeter, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.361336.

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50

McGeever, Michael K. "Design of a very high speed dynamic RAM in gallium arsenide for an ATM switch /." Title page, contents and abstact only, 1995. http://web4.library.adelaide.edu.au/theses/09PH/09phm1449.pdf.

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