Tesi: "Molecular beam epitaxy"

1

Leong, Weng Yee. "Silicon molecular beam epitaxy". Thesis, London Metropolitan University, 1985. http://repository.londonmet.ac.uk/3359/.

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This thesis reports on the techniques used in the growth and doping of Si-MBE layers prepared in a commercial molecular beam growth system and in the evaluation of their electrical and crystallographic properties. A number of technological problems associated with flux monitoring, the flaking of excess Si deposits and the use of closed-cycle He cryopumps during system bakeout were addressed. The electrical and crystallographic qualities of the undoped and doped Sl-MBE materials were assessed using preferential defect etching, four-point probe and Hall measurements, electrochemical CV profiling. Auger electron surface analysis, transmission electron microscopy (TEM), secondary ion mass spectroscopy (SIMS) analysis, spreading resistance measurement, and photoluminescence. The basic material grown was found to be of high quality and comparable to the Si-MBE material grown in other laboratories. Two electrically active contaminants, boron and phosphorus, were identified in our materials. The boron contamination was observed to occur at the substrate/epitaxial interface where the presence of an oxide layer prior to growth was apparently critical for its accumulation. Two new techniques in co-evaporatIve doping in Si-MBE are reported. The use of co-evaporated boron doping was Investigated enabling the growth of Sl-MBE material with bulk-like mobilities and carrier concentrations up to 1x10(to the power of 20) cm(to the power of -3) and giving excellent dopant profile control over a range of growth temperatures. The second technique called Potential Enhanced Doping (PED) involves applying a substrate potential during layer growth which enhances Sb dopant incorporation coefficient by up to a factor of 1000. Doping transitions were obtained by stepping the substrate potential. Using the PED technique, a maximum Sb dopant concentration of 2-3x10(to the power of 19) cm(to the power of -3) at 850°C and dopant transitions as abrupt as 200A/decade were achieved. Possible mechanisms for the observed PED effect are presented.

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2

Benz, Rudolph G. II. "Surface growth kinetics in molecular beam epitxay and gas source molecular beam epitaxy of CdTe". Diss., Georgia Institute of Technology, 1992. http://hdl.handle.net/1853/30421.

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3

Ericsson, Leif. "Silicon/Germanium Molecular Beam Epitaxy". Thesis, Karlstad University, Division for Engineering Sciences, Physics and Mathematics, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-146.

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Molecular Beam Epitaxy (MBE) is a well-established method to grow low-dimensional structures for research applications. MBE has given many contributions to the rapid expanding research-area of nano-technology and will probably continuing doing so. The MBE equipment, dedicated for Silicon/Germanium (Si/Ge) systems, at Karlstads University (Kau) has been studied and started for the first time. In the work of starting the system, all the built in interlocks has been surveyed and connected, and the different subsystems has been tested and evaluated. Service supplies in the form of compressed air, cooling water and electrical power has been connected. The parts of the system, their function and some of the theory behind them are described.

The theoretical part of this master’s thesis is focused on low-dimensional structures, so-called quantum wells, wires and dots, that all are typical MBE-built structures. Physical effects, and to some extent the technical applications, of these structures are studied and described.

The experimental part contains the MBE growth of a Si/Ge quantum well (QW) structure and characterisation by Auger Electron Spectroscopy (AES). The structure, consisting of three QW of Si0,8Ge0,2 separated by thicker Si layers, was built at Linköpings University (LiU) and characterised at Chalmers University of Technology (CTH). The result of the characterisation was not the expected since almost no Ge content could be discovered but an extended characterisation may give another result.

Keywords: Silicon, Germanium, Molecular Beam Epitaxy, MBE, Quantum wells

Molecular Beam Epitaxy (MBE) är en väl etablerad metod när det gäller tillverkning av låg-dimensionella strukturer för forskningsändamål och lämpar sig väl för användning inom det expanderande forskningsområdet nanoteknologi. MBE utrustningen vid Karlstads universitet (Kau), som är avsedd för kisel/germanium (Si/Ge) strukturer, har studerats och startats för första gången. Under studien av systemet har alla inbyggda förreglingar utretts och anslutits och de olika delsystemen har testats och utvärderats. Tryckluft, kylvatten och el har utretts och anslutits. Systemets delar, deras funktion och i viss mån den bakomliggande teorin har studerats.

Den teoretiska delen av detta arbete är inriktad mot låg-dimensionella strukturer d.v.s. kvant brunnar, kvanttrådar och kvantprickar, som alla är strukturer lämpliga för framställning i MBE processer. De fysikaliska effekterna och i viss mån de tekniska tillämpningarna för dessa strukturer har studerats.

Den experimentella delen består av MBE tillväxt av en Si/Ge kvantbrunn-struktur och karakterisering m.h.a. Auger Electron Spectroscopy (AES). Tillväxten av strukturen, som består av tre kvantbrunnar av Si0,8Ge0,2 separerade av tjockare Si-lager, utfördes på Linköpings Universitet (LiU) och karakteriseringen utfördes på Chalmers Tekniska Högskola (CTH). Resultatet av karakteriseringen var inte det förväntade då knappast något Ge innehåll kunde detekteras men en utökad undersökning skulle kanske ge ett annat resultat.

Sökord: Kisel, germanium, Molecular Beam Epitaxy, MBE, kvantbrunn

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4

鄭聯喜 e Lianxi Zheng. "Growth kinetics of GaN during molecular beam epitaxy". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2001. http://hub.hku.hk/bib/B31242741.

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5

Pindoria, Govind. "Silicon molecular beam epitaxy : doping and material aspects". Thesis, University of Warwick, 1990. http://wrap.warwick.ac.uk/106729/.

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Silicon Molecular Beam Epitaxy (Si-MBE) allows independent control over the dopant and matrix species, offering the possibility of engineering device structures with resolution down to the monolayer level. However, significant improvements in material quality and doping capability are essential before the potential of the growth technique for applications in VLSI technologies and in evaluating new device designs can be assessed. Three key areas have been identified in this study, where advances were considered feasible in the time scale of this project: particulate contamination, the modelling of the co-evaporation dopant incorporation process and an evaluation of a new dopant in Si-MBE, phosphorus. A fourth area, that of metallic contamination, was also investigated. Particulate contamination in Si-MBE epilayers is of increasing concern, as the possible applications of this layer growth technology to VLSI are assessed. A systematic study of several hundred epilayers correlated the particulate contamination in the epilayers with the high electron flux in the deposition region arising from the electron beam evaporator and with the unstable excess silicon deposits in the growth chamber. Reduction of silicon accumulation in the deposition zone by containment of the silicon flux significantly reduces particulate densities in the epilayers. Two types of particulate-related features have been identified. The first type thought to be due to microscopic particulates is decorated by crystallographic defects, whereas the second type, which is free of these defects, appears to be related to shadowing by larger particulates. A correlation in the densities of both types of particulate defects in epilayers grown under a variety of experimental conditions suggests a common source. The incorporation of dopants in Si-MBE has proven to be the most difficult aspect of this growth technology. In this study it is shown that the atomic size of a dopant relative to the matrix, is the key parameter which determines whether or not a dopant exhibits surface accumulation behaviour during molecular beam epitaxy. Specifically, surface accumulation only occurs If the dopant atoms are larger than those of the matrix atom substituted. In compound and alloy matrix systems, this size effect strongly influences the net site occupation of a dopant, a process previously believed to be dominated by site availability. The physical basis of this phenomenon is discussed with particular reference to theories of equilibrium surface segregation and the nature of the surface stress. Although p-type doping in Si-MBE with boron is now well established, allowing high doping concentrations and good dopant control, n-type doping using antimony has not matched these achievements, the problems becoming acute at low growth temperatures, (S 500°C). A possible alternative is the use of phosphorus instead of antimony. In this study the first phosphorus doped Si-MBE epilayers were grown, using a tin phosphide source. Bulk-like mobilities were demonstrated. The behaviour of phosphorus as a function of growth parameters and of 'potential enhanced doping' indicates a non-unity, almost growth temperature independent incorporation efficiency. Preliminary evidence indicates that phosphorus does not accumulate on the growing silicon surface, in line with the predictions of the empirical model. Metallic impurities can have a variety of influences on semiconducting devices, the majority of them detrimental. A preliminary investigation into the levels of metallic impurities in MBE grown silicon was carried out and a methodology developed aimed at reducing these levels.

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6

Sherman, Edward. "Renormalised field theory for ideal molecular-beam epitaxy". Thesis, Imperial College London, 2013. http://hdl.handle.net/10044/1/10961.

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In this thesis an overview is given of the renormalisation group as it is applied to equilibrium systems; the methods of field theory are extended to non-equilibrium systems, described by a Langevin equation in the stead of a Hamiltonian; this analysis is applied to a well known model of surface growth driven by molecular-beam epitaxy. The renormalisation group is a celebrated technique in both hard and soft condensed matter physics for probing the asymptotic behaviour of a model, though in this thesis no examination is made of quantum effects. Several distinct methods exist under the banner of renormalisation, most famously the approaches of Wilson and field theory. The renormalisation group is explored through a comparison of these approaches. The approach of field theory, with its methods being applied to an equilibrium system where a model is defined by a Hamiltonian, can be extended to analyse non-equilibrium systems, where a model is described by a Langevin equation. One class of the non-equilibrium condensed matter systems which have received extensive attention is that of surface growth. For the last two decades the Villain-Lai-Das Sarma equation has been used to understand conserved surface growth processes such as molecular-beam epitaxy. However, the theory has some aspects that seem incomplete. The mound formation observed experimentally and numerically lacks a complete theoretical narrative for its mechanism. Also, no clear picture has emerged over a disagreement in the literature about the alleged exactness of scaling relations. Using field theory to analyse the original derivation of the Villain-Lai-Das Sarma equation reveals that terms responsible for mound formation are generated under renormalisation, further these terms should have been included initially on symmetry grounds. It is possible to recover several widely studied Langevin equations at the trivial fixed point of the full theory, allowing a more complete theoretical picture to be presented for conserved epitaxial surface growth.

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7

Zheng, Lianxi. "Growth kinetics of GaN during molecular beam epitaxy". Hong Kong : University of Hong Kong, 2001. http://sunzi.lib.hku.hk/hkuto/record.jsp?B23316639.

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8

Jabeen, Fauzia. "III-V semiconducting nanowires by molecular beam epitaxy". Doctoral thesis, Università degli studi di Trieste, 2009. http://hdl.handle.net/10077/3097.

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2007/2008
This thesis is devoted to the study of the growth of III-V nanowires (NWs) by catalyst assisted and catalyst free molecular beam epitaxy (MBE). The nanostructures have been routinely characterized by scanning electron microscopy (SEM) and, to a minor extent by transmission electron microscopy (TEM). X-ray photoemission spectroscopy (XPS), scanning photoemission microscopy (SPEM), extended X-ray absrorption fi ne structure analysis (EXAFS), photoluminescence (PL) and trans- port measurements have given an important contribution on specifi c topics. The first section of this thesis reports on GaAs, InAs, and InGaAs NWs growth by Au assisted MBE. A substrate treatment is proposed that improves uniformity in the NWS morphology. Thanks to a careful statistical analysis of the NWs shape and dimensions as a function of growth temperature and duration, evidence is found of radial growth of the NWs taking place together with the axial growth at the tip. This eff ect is interpreted in term of temperature dependent diff usion length of the cations on the NWs lateral surface. The control of the NWs radial growth allowed to grow core shell InGaAs/GaAs NWs, displaying superior optical quality. A new procedure is proposed to protect NWs surface from air exposure. This procedure allowed to perform ex-situ SPEM studies of electronic properties of the NWs. The second part of this thesis is devoted to Au-free NWs growth. GaAs and InAs NWs were successfully grown for the first time using Mn as catalyst. Incorporation of Mn in the NW is studied using EXAFS technique. It is shown that Mn atoms are incorporated in the body of GaAs NWs. Use of low growth temperature is suggested in order to improve the Mn incorporation inside GaAs NWs and obtain NWs with magnetic properties. Finally, growth of GaAs and InAs NWs on cleaved Si subtrate is demonstrated without the use of any outside metal catalyst. Two kinds of nanowires have been obtained. The experimental findings suggest that the two types of nanowires grow after di fferent growth processes.
Questa tesi e' dedicata allo studio della crescita di nanofili di semiconduttori III- V tramite epitassia da fasci molecolari (MBE) assistita da catalizzatore e senza l'uso di catalizzatori. Le nanostrutture sono state caratterizzate sistematicamente tramite microscopia elettronica a scansione (SEM), e in maniera minore microscopia elettronica in trasmissione (TEM). Altre tecniche come la spettroscopia di fotoemissione da raggi x (XPS), la microscopia da fotoemissione in scansione (SPEM), la spettroscopia di assorbimento x (in particolare la extended X-ray absorpition fine structure analysis (EXAFS)) la fotoluminescenza (PL), e il trasporto elettrico hanno dato importanti contributi su problematiche specifiche. La prima parte di questa tesi riguarda la crescita di nanofili di GaAs, InAs e InGaAs tramite MBE assistita da oro. Viene proposto un trattamento del substrato che migliora nettamente l'omogeneita' morfologica dei nanofili. Grazie ad un'attenta analisi statistica della forma e delle dimensioni dei nanofili in funzione della temperatura e del tempo di crescita e' stata dimostrata la crescita radiale dei nanofili, che avviene insieme alla crescita assiale che ha luogo alla punta del nanofilo. Le osservazioni sperimentali sono state interpretate in termini di dipendenza dalla temperatura della lunghezza di diffusione dei cationi sulle super ci laterali dei nanofili. Il controllo della crescita radiale ha permesso di crescere nanofili di InGaAs/GaAs core shell, costituiti cioe' da una anima centrale di InGaAs (core) e uno strato esterno di GaAs (shell) , che hanno dimostrato eccellente qualita' ottica. Viene quindi proposta una nuova procedura per proteggere la super ficie dei nanofili durante l'esposizione all'aria. Grazie a questa e' stato possibile realizzare ex-situ uno studio SPEM delle proprieta' elettroniche dei nanofili. La seconda parte della tesi riguarda la crescita di nanofili senza l'uso di oro. Viene per la prima volta dimostrata la possibilita' di crescere nanofili di GaAs e InAs usando il manganese come catalizzatore. L'incorporazione del Mn come impurezza nei nanofili e' stata studiata tramite EXAFS. Le misure hanno dimostrato che atomi di Mn sono effettivamente incorporate nel corpo dei nano fili. La crescita delle nanostrutture a temperatura piu' bassa potrebbe migliorare qualitativamente l'incorporazione del Mn e permettere la crescita di nanofili con proprieta' magnetiche. Viene in fine dimostrata la crescita di nanofili di GaAs e di InAs senza l'utilizzo di materiali diversi da quelli costituenti il semiconduttore. Tale risultato e' ottenuto su superfici sfaldate di silicio. Sono state osservate nanostrutture di due tipi, che sulla base dei dati sperimentali sembrano essere dovuti a due diversi meccanismi di crescita.
XXI Ciclo
1977

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9

Devine, R. L. S. "Some kinetic and thermodynamic aspects of molecular beam epitaxy". Thesis, University of Glasgow, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.378055.

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10

Sadofiev, Sergey. "Radical-source molecular beam epitaxy of ZnO-based heterostructures". Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2009. http://dx.doi.org/10.18452/16054.

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Im Rahmen der Dissertation wurden molekularstrahlepitaktische Verfahren zur Züchtung von Hetero-und Quantenstrukturen auf der Basis der Gruppe II-Oxide entwickelt. Insbesondere wurde ein Wachstumsregime weit entfernt vom thermischen Gleichgewicht etabliert, welches die Mischung von CdO und MgO mit ZnO in phasenreiner Wurtzitstruktur ermöglicht, wobei die Gleichgewichtslöslichkeitsgrenzen dramatisch überschritten werden. In den Mischkristallen kann die Bandlücke kontinuierlich von 2.2 bis 4.4 eV eingestellt werden. Das Wachstum verläuft in einem zweidimensionalen Modus und resultiert in atomar glatten Ober- und Grenzflächen. Ausgeprägte RHEED- Intensitätsoszillationen erlauben die atomlagengenaue Kontrolle der Schichtdicken und somit die Realisierung wohl-defi- nierter Einzel- und Mehrfachquantengrabenstrukturen. Diese zeichnen sich durch eine hohe Photolumineszenzquantenausbeute im gesamten sichtbaren Spektralbereich aus. Laseraktivität kann vom UV bis zum grünen Wellenlängenbereich bei Zimmertemperatur erzielt werden. Das Potenzial dieser Quantenstrukturen in Hinblick auf ihre Anwendung in opto-elektronischen Bauelementen wird diskutiert.
This work focuses on the development of the novel growth approaches for the fabrication of Group II-oxide materials in the form of epitaxial films and heterostructures. It is shown that molecular-beam epitaxial growth far from thermal equilibrium allows one to overcome the standard solubility limit and to alloy ZnO with MgO or CdO in strict wurtzite phase up to mole fractions of several 10 %. In this way, a band-gap range from 2.2 to 4.4 eV can be covered. A clear layerby- layer growth mode controlled by oscillations in reflection high-energy electron diffraction makes it possible to fabricate atomically smooth heterointerfaces and well-defined quantum well structures exhibiting prominent band-gap related light emission in the whole composition range. On appropriately designed structures, laser action from the ultraviolet down to green wavelengths and up to room temperature is achieved. The properties and potential of the "state-of-the-art" materials are discussed in relation to the advantages for their applications in various optoelectronic devices.

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11

Ratsch, Christian. "Morphological stability of facet growth on patterned substrates". Thesis, Georgia Institute of Technology, 1990. http://hdl.handle.net/1853/27549.

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12

Tong, Wusheng. "Chemical beam epitaxial growth of ZnS : growth kinetics and novel electroluminescent strutures". Diss., Georgia Institute of Technology, 1996. http://hdl.handle.net/1853/31012.

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13

Triplett, Gregory Edward Jr. "Process modeling of InAs/AISb materials for high electron mobility transisitors grown by molecular beam epitaxy". Diss., Georgia Institute of Technology, 2004. http://hdl.handle.net/1853/9458.

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14

Pang, Ka-yan. "Nucleation and growth of GaN islands by molecular-beam epitaxy". Click to view the E-thesis via HKUTO, 2005. http://sunzi.lib.hku.hk/hkuto/record/B36776543.

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15

Whitwick, Michael Brian. "Surface evolution during gallium arsenide homoepitaxy with molecular beam epitaxy". Thesis, University of British Columbia, 2009. http://hdl.handle.net/2429/17455.

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GaAs grown with MBE is the basis for many useful optoelectric devices. Measurements are presented of the smoothing of patterned and randomly roughened GaAs surfaces during homoepitaxy over a large range of Ga flux, substrate temperatures, arsenic fluxes, and Bi surfactant. The bulk of these measurements were taken by in-situ elastic light scattering or ex-situ AFM. These measurements provide experimental support for a non-linear continuum growth model that has been derived analytically from basic atomic level phenomena that occur in epitaxial film growth. During epitaxial growth the smoothing is observed to change in nature as the surface amplitude decreases. One of the regimes of smoothing is associated with the linear smoothing coefficients from the physically based non-linear continuum growth equation. The temperature and growth rate dependence of the smoothing coefficients are presented and found to be in good agreement with predictions from the continuum growth model. A key parameter in the continuum growth equation, the density of atomic steps, is measured independently using AFM. The step density, which agrees with theoretical predictions, is used to compute smoothing coefficients and is shown to be in agreement with the light scattering measurements. Complex shapes are observed for epitaxial growth on patterned GaAs substrates. Two characteristic surface morphologies were observed. The first is characterized by downward V-shaped cusps and rounded mounds caused by non-linear smoothing. The second morphology is similar, however the symmetry of the surface structure was inverted. This surface morphology has not been previously observed in GaAs. Step edge attachment was found to be the driving mechanism that produced both of these morphologies. Bismuth is observed to act as a surfactant in GaAs homoepitaxy. While Bi assisted growth is found to decrease the overall surface roughness, it is also found to alter the characteristics of the surface morphology. Notably, roughness at low spatial frequency was increased with the addition of Bi, while at high spatial frequency roughness was decreased. Significant changes to the shape evolution of patterned substrate are also observed when Bi is added to GaAs epitaxial growth.

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16

Moseley, Michael William. "Study of III-nitride growth kinetics by molecular-beam epitaxy". Diss., Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/47641.

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Since the initial breakthroughs in structural quality and p-type conductivity in GaN during the late 1980s, the group-III nitride material system has attracted an enormous amount of interest because of its properties and applications in both electronics and optoelectronics. Although blue light-emitting diodes have been commercialized based on this success, much less progress has been made in ultraviolet emitters, green emitters, and photovoltaics. This lack of development has been attributed to insufficient structural and electrical material quality, which is directly linked to the growth of the material. The objective of this work is to expand the understanding of III-nitride growth towards the improvement of current device capabilities and the facilitation of novel device designs. Group-III nitride thin films are grown by molecular-beam epitaxy in a pulsed, metal-rich environment. The growths of nitride binaries and ternaries are observed in situ by transient reflection high-energy electron diffraction (RHEED) intensities, which respond to the behavior of atoms on the growing surface. By analyzing and interpreting these RHEED signatures, a comprehensive understanding of nitride thin film growth is obtained. The growth kinetics of unintentionally doped GaN by metal-rich MBE are elucidated, and a novel method of in situ growth rate measurement is discovered. This technique is expanded to InN, highlighting the similarity in molecular-beam epitaxy growth kinetics between III-nitride binaries. The growth of Mg-doped GaN is then explored to increase Mg incorporation and electrical activation. The growth of InxGa1-xN alloys are investigated with the goal of eliminating phase separation, which enables single-phase material for use in photovoltaics. Finally, the growth of unintentionally doped and Mg-doped AlGaN is investigated towards higher efficiency light emitting diodes. These advancements in the understanding of III-nitride growth will address several critical problems and enable devices relying on consistent growth in production, single-phase material, and practical hole concentrations in materials with high carrier activation energies.

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17

Evans, R. J. "Electronic properties of molecular beam epitaxy structures prepared by regrowth". Thesis, University of Cambridge, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.598882.

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This dissertation is concerned with the fabrication and physics of Molecular Beam Epitaxy (MBE) regrown semiconductor devices. I use the term regrown to refer to a structure which has been fabricated by MBE growth over a surface which has been ex-situ patterned. The structures presented in this dissertation can be subdivided into two broad categories: the narrow facet channels and the patterned back-gates. The narrow facet channels form part of a new class of devices, where the amphoteric nature of silicon dopant in the AlGaAs lattice is used to create lateral confinement. Growth of a GaAs A1GaAs heterostructure over a (311)A substrate, which is etched to expose a narrow (100) facet, results in the formation of a narrow two dimensional electron gas (2DEG) on the facet which is interspersed between two, two dimensional hole gases (2DHGs). The transport characteristics of the narrow 2DEG can be modulated by applying voltage to the adjacent hole gases, i.e. biasing either or both of the two dimensional p-n junctions formed between the 2DEG and 2DHGs. The actual width of the electron channel was found to be considerably smaller that the lithographic facet width. Theoretical modelling showed that this was a result of the fabrication and growth of the sample and not the electro-statics of the system. The inverse structure of a narrow 2DHG interspersed between two 2DHGs was also fabricated. The transport through the narrow 2DHG could be modulated in a similar manner. The patterned back-gated structures are the simplest illustration of the fabrication technique and are discussed first in the dissertation. The patterned back-gate is formed as islands of n⁺ GaAs on an undoped GaAs substrate. Subsequently grown continuous layers are therefore guided in three dimensions over a wafer surface with regions of differing semiconductor compositions. This is a wafer scale fabrication technique, which completely dismisses the need for complicated lithography. The patterned back-gate was used to distinguish between the presence of an extended state formed between two 2DEGs and a second subband formed in one of the 2DEGs. The second subband was then used as a probe to characterise the regrowth interface. The series of back-gated long split gates showed quantisation plateaux illustrating the high quality of the samples fabricated using the regrowth technique.

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18

吳誼暉 e Yee-fai Ng. "Heteroepitaxial growth of InN on GaN by molecular beam epitaxy". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2002. http://hub.hku.hk/bib/B29797846.

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19

Pang, Ka-yan, e 彭嘉欣. "Nucleation and growth of GaN islands by molecular-beam epitaxy". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2005. http://hub.hku.hk/bib/B36776543.

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20

Kan, Xin, e 阚欣. "Growth of Bi2Se3 on Si substrate by molecular beam epitaxy". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2011. http://hub.hku.hk/bib/B46474687.

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21

Lewis, Ryan B. "Molecular beam epitaxy growth technology and properties of GaAsBi alloys". Thesis, University of British Columbia, 2014. http://hdl.handle.net/2429/46478.

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In this thesis, molecular beam epitaxy (MBE) technology and the MBE growth of GaAsBi are investigated. MBE is a non-equilibrium technique whereby precisely controlled molecular beams are deposited onto a heated substrate at temperatures much lower than for equilibrium growth techniques. A novel closed-cycle cooling setup is implemented to replace liquid nitrogen (LN₂) cooling of the MBE cryo-shroud. The temperature dependence of cryopanel pumping is explored, and GaAs and AlGaAs layers grown using the new cooling setup and with LN₂ cooling of the shroud are characterized. Strong AlGaAs photoluminescence and low impurity concentrations indicate closed-cycle cooling is a promising cost-saving technique for MBE. The relatively unexplored III-V-Bi family of alloys is an exciting frontier of III-V semiconductor alloy exploration. The GaAsBi alloy exhibits many novel properties, including an unparalleled bandgap reduction per change in the size of the crystal lattice, presenting a wide range of potential device applications. A systematic study of the dependence of Bi incorporation on MBE growth conditions is presented. Bi incorporation is found to rapidly increase as the As₂:Ga flux ratio is lowered to 0.5 and saturate for lower flux ratios. This indicates Bi incorporation is sensitive to the surface stoichiometry. A GaAsBi growth model is proposed where Bi from a wetting layer incorporates on surface sites which are terminated by Ga. Low growth temperatures are required as the weak Bi-Ga incorporation bond can be broken thermally, ejecting Bi back to the wetting layer. GaAsBi layers with up to 21.8% Bi, record Bi-content, were grown at temperatures as low as 200C. These layers have up to 2.6% mismatch from the GaAs substrates and show unusually large critical thicknesses for relaxation, a result of the low growth temperature. Optical absorption measurements on pseudomorphic GaAsBi layers with up to 18.7% Bi show the bandgap decreases strongly with increasing Bi-content, reaching 0.5 eV at 18.7% Bi. Si-doped n-GaAsBi layers with up to 4% Bi show the concentration of acceptor states increases rapidly with increasing Bi-content. The acceptor concentration is equal to that of closed Bi3 clusters, suggesting they are the source of deep acceptor states in GaAsBi.

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22

Smith, David Warren. "Material quality issues in Si and SiGe molecular beam epitaxy". Thesis, University of Warwick, 1993. http://wrap.warwick.ac.uk/51967/.

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MBE growth of Si and SiGe allows a high degree of control over doping profiles and of strained alloy semiconductor growth. The structures that can be formed as a result have many potential applications for new solid state physics studies and for commercial device exploitation. However, the electrical material quality of MBE grown Si and SiGe is a function of many complex, interrelated processes and has not been extensively studied. In this work, the objectives have been to study the electrical quality of as-grown Si as a function of growth temperature and to investigate the material requirements for high mobilities (at low temperatures) in SiGe channel 2D hole gases. The former has been achieved by room temperature measurements of the generation lifetime using low temperature oxides, and the latter by parallel transport measurements at temperatures of 3K to 20K. For the first time, generation lifetimes, τg, have been measured by an MOS capacitance transient technique where all post growth processing temperatures have been below the growth temperature, Ts. These lifetimes are believed to reflect as-grown Si quality. Values of τg in Si, grown in a V80 MBE system, were found to be ~200 ns for Ts in the range 600 to 800 C. This study was limited by transient effects (that are believed to result from oxide breakdown) and no Ts dependence could be confirmed. A further study of Si grown in a V90S system revealed a complex, but repeatable, dependence of τg on Ts, with a minimum of τg=10 ns at mid-range Ts (~600 C). At high and low Ts, values of τg=12 μs were measured, as compared to values of tg X10 μs in control substrates. Importantly, post growth annealing has indicated that the Ts dependence is a not a thermal effect, i.e. it is growth related. It has been necessary to develop some techniques for device processing in order to preserve the integrity of MBE structures. Some of these techniques were applied to the processing of MBE grown pn diodes, and values of rg measured by current- and capacitance-voltage methods. These values vary greatly, ranging from 1 ns to 10 μs from epilayer to epilayer and also varied by up to an order of magnitude across an epilayer. Values of tg obtained from control substrates were also low and inconsistent; therefore, this is likely to be due to the alteration of material quality during processing. The lifetime - Ts dependence is reconcilable with the as-grown results, but provides no confirmation due to the processing induced effects. The only high temperature process used was a 1000 C, 15 second implantation activation anneal, which was assessed by the MOS technique, and shown not to alter material quality. All previous studies on SiGe channel 2D hole gases had reported relatively low mobilities, which were thought to be limited by alloy scattering. The material quality studies on this system, described here, have resulted in a maximum low temperature mobility greater than twice that previously reported for these structures. At the start of this study, mobilities were found to be limited by Cu contamination in the SiGe channel. The Cu was observed to redistribute in the structure as a result of a growth interruption and higher mobilities were obtained. Post growth annealing studies have indicated that this is a growth related effect. Modifications made to the growth technology significantly reduced the Cu concentration and further increased the mobilities. The 4K 2D hole gas mobility is shown to increase with increasing growth temperature up to 640 C, which has been associated with a reduction in interface charge scattering and, again, post growth annealing has indicated that this is associated with a growth related process. By further increasing growth temperature to 850 C, a maximum mobility of ~9000 cm2V-1s-1 was obtained. At higher growth temperatures, mobilities degraded. Experiments, in which the SiGe channel width and 2D carrier concentration were varied, have indicated that the mobility, at high growth temperatures, is limited by both interface charge and long range ripple at the upper SiGe/Si interface, which can be described in terms of interface roughness scattering.

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23

Isakov, I. "Semiconductor nanowires grown by molecular beam epitaxy for electronics applications". Thesis, University College London (University of London), 2015. http://discovery.ucl.ac.uk/1463378/.

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One-dimensional nanostructures such as semiconductor nanowires are very attractive for application in next generation electronics. This work presents an experimental study of InAs-based and ZnO-based nanowires grown by molecular beam epitaxy for electronics applications. InAs, InAsP and InAsSb nanowires were grown self-catalytically on silicon. Phosphorus incorporation was studied by means of HRTEM, XRD, EDX and PL. The phosphorus incorporation rate was shown to be 10 times smaller than that of arsenic. InAs and InAsP nanowires exhibit the wurtzite structure with a high density of stacking faults and phase boundaries. Conversely, InAsSb nanowires exhibit the zincblende structure with the density of stacking faults decreasing as the antimony content increases. Antimony incorporation and reduction of the stacking fault density improves the nanowire mobility. ZnO and ZnMgO nanowires and ZnO/ZnMgO core-shell nanowire heterostructures were grown by plasma-assisted molecular beam epitaxy on various substrates with gold particles as a growth catalyst. Nanowire growth was shown to occur only at temperatures between 700 and 850 C and Zn pressures between 1 and 3 10 7 Torr. A two-step growth procedure on silicon was implemented to increase the yield of nanowire growth. Mg incorporation was shown to be 4 times smaller than that of Zn. At Mg content higher than 20 %, MgZnO rocksalt phase segregation is observed in the as-grown samples. Core-shell nanowires were fabricated by growing the shell at a lower temperature of 500 C. ZnO nanowire field effect transistors were fabricated and optimised. High- and low-temperature transport measurements allowed determination of the bulk nanowire and contact properties. Nanowires grown on sapphire and silicon were compared. Nanowires grown on sapphire exhibit an extra donor that determines their low temperature conductivity and give a wider photoluminescence band-edge emission peak. A novel technique to measure the spectrum of deep traps in nanowire field effect transistors was implemented to study ZnO nanowires.

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24

He, Lei. "III-nitride Semiconductors Grown By Plasma Assisted Molecular Beam Epitaxy". VCU Scholars Compass, 2004. http://scholarscompass.vcu.edu/etd/1019.

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III-nitride semiconductors are of great interest owing to their commercial and military applications due to their optoelectronic and mechanical properties. They have been synthesized successfully by many growth methods. Among them, molecular beam epitaxy (MBE) is a promising epitaxial growth method owing to precise control of growth parameters, which significantly affect the film properties, composition, and thickness. However, the understanding of growth mechanism of III-nitride materials grown in this growth regime is far from being complete.In this dissertation, GaN and AIGaN growth mechanism under metal-rich conditions were investigated. The Ga surface desorption behavior during the growth was investigated systematically using reflection high-energy electron diffraction (RHEED). It was found that desorption of Ga atoms from the (0001) GaN surfaces under different III-V ratios deviates from the zeroth-order kinetics in that the desorption rate is independent of the coverage of adsorbed atoms. The desorption energies of Ga are determined to be 2.76 eV with the Ga coverage closing to 100%, 1.89 eV for a ~45% coverage, and 0.82 eV for a 10% coverage, as monitored by the change of the RHEED specular beam intensity during growth. In addition, the GaN surface morphology under different III-V ratios on porous templates matches the dependence of Ga desorption energy on the metal coverage, and III/V ratio dominates the growth mode. In a related AIGaN growth mechanism study, a competition between A1 and Ga atoms to incorporate into the film was found under metal-rich conditions. Employing this mechanism, A1xGa1-xN layers with precisely controlled A1 mole fraction, x in the range 0xxGa1-xN films was determined to be about 1 eV. The A1xGa1-xN layers grown under metal-rich conditions, as compared to that under N-rich conditions, have a better structural and optical quality. Employing A1xGa1-xN layers grown under metal-rich conditions, a lateral geometry GaN/A1GaN MQW-based photodetector was fabricated. It exhibited a flat and narrow spectral response in the range of 297~352 nm in the backillumination configuration.

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25

Baklenov, Oleg. "Molecular beam epitaxy of quantum dots for high speed photodetectors /". Digital version accessible at:, 1999. http://wwwlib.umi.com/cr/utexas/main.

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26

Ng, Yee-fai. "Heteroepitaxial growth of InN on GaN by molecular beam epitaxy /". Hong Kong : University of Hong Kong, 2002. http://sunzi.lib.hku.hk/hkuto/record.jsp?B25212175.

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27

Richards, Robert D. "Molecular beam epitaxy and characterisation of GaAsBi for photovoltaic applications". Thesis, University of Sheffield, 2014. http://etheses.whiterose.ac.uk/7549/.

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GaAsBi is a promising candidate material for a 1 eV junction for multi-junction photovoltaics, as well as having many other potential applications in areas such as telecommunications and spintronics. The growth of GaAsBi has proven problematic due to the large size and low electronegativity of the Bi atom, and this has hindered its development. In this thesis, the growth and material characterisation of GaAsBi is presented. A systematic series of bulk GaAsBi samples were grown by molecular beam epitaxy to investigate the effects of growth temperature, As flux and As species on the bismuth content and optical quality of the samples. Two growth regimes became apparent: a temperature limited regime in which the Bi content is limited by the miscibility of GaAs and GaBi, and a Bi flux limited regime in which the Bi incorporation coefficient approaches unity. The production of good quality GaAsBi was shown to require near a near stoichiometric Ga:As atomic flux ratio. The dependence of Bi content on As species was explained by considering the results of Foxon and Joyce, which show the necessary desorption of 50 % of the incident As4 flux during GaAs growth. The optical quality of GaAsBi was shown to have no dependence on the As species used during growth. Using the expertise gained from the growth of bulk GaAsBi, a series of GaAsBi/GaAs multiple quantum well p-i-n diodes was grown and characterised. Preliminary results showed that good quality structures were grown with photoluminescence peaks at around 1050 nm. The samples containing a large number of quantum wells showed signs of strain relaxation and a redshift and attenuation of their photoluminescence spectra. Calculations of the effects of strain relaxation and loss of quantum confinement on the photoluminescence emission wavelength, suggest that both factors contribute to the observed redshift. The onset of strain relaxation in these samples appeared to occur at a similar average strain to InGaAs/GaAs samples reported in the literature. These results suggest that GaAsBi could provide a competitive alternative to InGaAs for high efficiency multi-junction photovoltaics.

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28

Kim, Dong Jun. "Novel Growth of IngaAs/GaAs Nanostructures by Molecular Beam Epitaxy". DigitalCommons@USU, 2009. https://digitalcommons.usu.edu/etd/258.

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This dissertation presents an extensive study of the epitaxial growth mechanism by a novel growth method. This novel growth method was developed at Utah State University and is a modification of the Stranski-Krastanov (S-K) growth mode. Our new growth method consists of a two-step process, low temperature growth and high temperature annealing. During low temperature growth, diffusion is minimized, resulting in the deposition of a pseudomorphic epilayer. During high temperature annealing, diffusion is induced from the pseudomorphic epilayer, resulting in the transformation of the epilayer into nanostructures. Benefits of this novel growth method are a significantly smaller segregation and suppressed intermixing due to the barrier wetting layer during sample growth. InGaAs nanostructures on GaAs(001) surfaces are examples of this new growth method. They were grown by molecular beam epitaxy (MBE) and analyzed using real-time reflection high energy electron diffraction (RHEED) and in situ scanning tunneling microscopy (STM). Our novel approach resulted in quantum dot chains and quantum dashes formed by annealing pseudomorphic layers of two different thicknesses of InGaAs on GaAs(001). These nanostructure shapes are different from those features formed by the conventional Stranski-Krastanov growth mode. The results indicate the potential to better understand nanostructures for future optoelectronic device applications.

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29

Zannier, Valentina. "ZnSe nanowires by molecular beam epitaxy: growth mechanisms and properties". Doctoral thesis, Università degli studi di Trieste, 2015. http://hdl.handle.net/10077/11134.

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2013/2014
This thesis is devoted to the study of the growth of Zinc Selenide (ZnSe) nanowires (NWs) by Au-assisted molecular beam epitaxy (MBE). The growth process consists in many steps which were individually investigated by means of in-situ and ex-situ spectroscopic and microscopic techniques. First, the formation of nanoparticles upon annealing of a thin Au film deposited on different substrates was studied by X-ray photoemission spectroscopy, grazing incident X-ray diffraction and scanning electron microscopy. The nanoparticles were used as seeds for the 1-dimensional ZnSe crystal growth by MBE through evaporation of Zn and Se from elemental solid sources. The obtained NWs were characterized by scanning and transmission electron microscopy and their optical properties were assessed by means of photoluminescence and cathodoluminescence measurements. This systematic investigation approach allowed us to understand the NWs growth mechanism and, as a consequence, to obtain the control over the NWs properties. Indeed, it was found that an interplay between substrate, seed particles and beam fluxes takes place and strongly affects the NWs growth mode. In particular, a chemical interaction between substrate and Au may occur during the annealing, changing chemical composition and physical state of the nanoparticles before the NWs growth. The vapour composition, i.e. the Zn-to-Se beam pressure ratio, can also modify the nanoparticles composition and the NWs growth mechanism. Therefore, by changing the growth conditions, it was possible to grow ZnSe NWs through different mechanisms, with important consequences on their properties, in terms of morphology, crystal quality and optical properties. Understanding the growth mechanism and its effects on the wires properties allowed us to achieve the control over the growth process and the selective growth of ZnSe nanowires with the desired properties. Vertically oriented ZnSe NWs with a defect-free hexagonal crystal structure were obtained on GaAs(111)B substrates, having either Au-Ga alloy nanoparticles or Au nanocrystals on their tips. Uniformly thin and straight blue-emitting ZnSe NWs were also grown on various substrates, after optimizing gold film thickness, annealing and growth temperature. The possible integration of such nanostructores in novel nanodevices was proposed and preliminary demonstrated.
XXVII Ciclo
1986

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30

Rajavel, Damodaran. "Molecular beam epitaxial and chemical beam epitaxial growth and doping studies of (001) CdTe". Diss., Georgia Institute of Technology, 1991. http://hdl.handle.net/1853/11129.

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31

Collins, Gregory Earl. "New molecular electronic materials: Gas phase chemical sensors and organic molecular beam epitaxy". Diss., The University of Arizona, 1992. http://hdl.handle.net/10150/186045.

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The trivalent metallophthalocyanines, GaPc-Cl and InPc-Cl, have been investigated with respect to: (1) their possible application as gas-phase chemical sensor coatings for the detection of O₂, NH₃ and NO₂; and (2) the development of a new class of molecular electronic materials based upon the epitaxial growth of these large organic molecules. UHV analyses of InPc-Cl coated interdigitated array transducers have indicated that impurity phthalocyanines (such as FePc, MnPc and CuPc) have a dramatic impact upon the electrical nature and responsivity of these devices toward various gas analytes. Each of the different gas analytes examined, O₂, NH₃ and NO₂, were found to possess at least two different types of chemisorption sites on the surface of these organic films. Chemical sensor devices prepared and characterized under vacuum (including quartz crystal microbalance, surface acoustic wave and interdigitated array transducer devices), were also examined within an atmospheric sensing chamber in order to assess their ultimate feasibility as chemical sensors. The simultaneous monitoring of both electrical and microgravimetric changes within these devices allowed for complimentary information to be obtained concerning the chemisorption events taking place on the surface of these materials. Photoelectrochemical metal modification of the surface of these phthalocyanines provided a means for further enhancing the response of the chemical sensors toward NH₃, while a modification of the phthalocyanine surface with reducing agents such as polyvinyl ferrocene and MnPc provided an analogous enhancement in sensitivity to NO₂. The epitaxial growth of InPc-Cl has been demonstrated on both bulk SnS₂(0001) and MBE grown SnS₂ on muscovite. The optical absorbance and photoaction spectra obtained from these highly ordered phthalocyanine films have, in some cases, been found to be as narrow as the solution absorption spectra for these materials (FWHM = 40-60 nm). The epitaxial growth of CuPc, perylene tetracarboxylic dianhydride, C₆₀ and coronene were demonstrated on the MoS₂(0001) surface, with specific models developed to explain the nature of these organic overgrowths on the metal dichalcogenide surface. The formation of highly ordered heterojunctions or bilayer films based upon various combinations of these organic semiconductor materials has also been investigated as a precursor to the development of organic superlattice structures.

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32

Shen, Xiu-Li. "Chemical beam epitaxial growth of (001) ZnS". Thesis, Georgia Institute of Technology, 1994. http://hdl.handle.net/1853/18896.

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33

Lee, Tae-Woo. "An experimental and theoretical study of InGaP-GaAs double heterojunction bipolar transistors". Thesis, University of Sheffield, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.324090.

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34

Pritchett, David Chu. "Novel III-Nitride growth by ultraviolet radiation assisted metal organic molecular beam epitaxy". Diss., Atlanta, Ga. : Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/28140.

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Thesis (M. S.)--Electrical and Computer Engineering, Georgia Institute of Technology, 2009.
Committee Chair: Doolittle, W. Alan; Committee Member: Carter, W. Brent; Committee Member: Ferguson, Ian T.; Committee Member: Frazier, A. Bruno; Committee Member: Rincon-Mora, Gabriel A.

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35

Trapp, Alexander [Verfasser]. "Molecular beam epitaxy of quantum dots on misoriented GaAs(111)B by droplet epitaxy / Alexander Trapp". Paderborn : Universitätsbibliothek, 2019. http://d-nb.info/1185570764/34.

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36

Lin, Jacob Che-Chen. "Fabrication of InAs/GaAs single quantum dots by molecular beam epitaxy". Thesis, University of Sheffield, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.487603.

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Quantum dots (QDs) are a class of semiconductor structure widely studied for their unique electronic and opto-electronic properties. Its extreme narrow line width property has been long predicted before first successful fabrication, and currently it is one of the main nano-structures used in light emitting devices. The QDs Idescribed here are engineered to form in a self-assembled manner where large quantities ofthem are produced at once. In the last decade, huge research efforts have been pumped ip.to controlling the property of the QD ensembles, such as areal density, wavelength, homogeneity and defect density. Towards the other extreme of the research interest, single QD fabrication is desirable for single electron and single photon devices, which are crucial tools both for quantum phenomenon observation and for the development ofquantum cryptography and quantum information processing. Two approaches are used to fabricate single QDs. In the micro-mesa approach areas on the dielectric mask are 'lectively opened so that the crystal structure is allowed to grow on the opened area. Usually the structures grown have a pyramidal shape. Choosing the base orientation correctly can result in pyramids with reducing top area and non-QD-growing sidewalls. Only a single QD would form at the apex of the pyramid if the pyramid size and maturity are well-controlled. The other approach described here is the micro-dimple approach. Since the formation of self-assembled QDs is a strain driven process, pin-point disturbance on a plain growth surface such as a dimple promotes QD nucleation on that point. Thus, a deposition of QD material with less than critical thickness may result in QD nucleation only on the dimples. For the micro-mesa approach, successful single QD growth has been performed in metal organic vapour phase epitaxy (MOVPE) and chemical beam epitaxy (CBE), and is demonstrated here in solid source molecular beam epitaxy (MBE). Performing lnAs/GaAs selective area QD growth in MBE appears to be problematic. The low GaAs growth selectivity between the dielectric mask and the GaAs epilayer in MBE destroys the shape of the pyramid grown. A combination of high growth temperature and low growth rate by periodic supply epitaxy (PSE) is used to reduce the polycrystalline fonnation on the mask. It is discovered that the polycrystals fonned on the dielectric mask reduce the neighbouring InAs QD areal density, whereas in MOVPE the dielectric mask increases the InAs QD areal density and/or height. Growing single QDs with the micro-dimple approach by MBE without atomic . hydrogen cleaning (ARC) is also investigated. During oxygen desorption in MBE, the native oxide on the processed sample fonns pits with a density as high as the selfassembled QDs and size comparable to the purposely made dimples. In order to realise a plain surface with only the dimples made during the fabrication processing, atomic hydrogen cleaning is usually employed to stop the pit fonnation during the oxygen desorption step. The alternative Ga beam supplement to reduce the pits is investigated and used in single QD fabrication by the micro-dimple approach in MBE.

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37

Sewell, Richard H. "Investigation of mercury cadmium telluride heterostructures grown by molecular beam epitaxy". University of Western Australia. School of Electrical, Electronic and Computer Engineering, 2005. http://theses.library.uwa.edu.au/adt-WU2005.0106.

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[Truncated abstract] Infrared radiation detectors find application in a wide range of military and civilian applications: for example, target identification, astronomy, atmospheric sensing and medical imaging. The greatest sensitivity, response speed, and wavelength range is offered by infrared detectors based on HgCdTe semiconductor material, the growth and characterisation of which is the subject of this thesis. Molecular Beam Epitaxy (MBE) is a versatile method of depositing layers of semiconductor material on a suitable crystalline substrate. In particular, MBE facilitates the growth of multilayer structures, thus allowing bandgap engineered devices to be realised. By modulating the bandgap within the device structure it is possible to improve the sensitivity or increase the operating temperature of photodetectors when compared to devices fabricated on single layer material. Furthermore, dual-band detectors may be fabricated using multi-layered HgCdTe material. The bulk of this thesis is concerned with the development of the MBE process for multilayer growth, from modelling of the growth process to characterisation of the material produced, and measurement of photoconductive devices fabricated on these wafers. In this thesis a previously published model of HgCdTe growth by MBE is reviewed in detail, and is applied to the growth of double layer heterostructures in order to determine the optimum method of changing the mole fraction between layers. The model has been used to predict the change in the temperature of the phase limit when the mole fraction and growth rate change suddenly as is the case during growth of an abrupt heterostructure. Two options for growth of an abrupt heterostructure were examined (a) modulating the CdTe flux and (b) modulating the Te flux. The change in the phase limit temperature between the layers was calculated as being 4:1±C for option (a) and 5:2±C for option (b) when growing a Hg(0:7)Cd(0:3)Te/Hg(0:56)Cd(0:44)Te heterostructure

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38

Shi, Min. "Growth of AlInN and zinc blende GaN by molecular beam epitaxy". Click to view the E-thesis via HKUTO, 2007. http://sunzi.lib.hku.hk/HKUTO/record/B39558873.

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39

Bone, Paul Adam. "Growth of (Ga, In)(N, As) alloys by molecular beam epitaxy". Thesis, Imperial College London, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.429487.

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40

Tok, Eng Soon. "Kinetic studies of GaAs growth and doping by molecular beam epitaxy". Thesis, Imperial College London, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.300412.

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41

彭澤厚 e Chak-hau Pang. "A study of Mg doping in GaN during molecular beam epitaxy". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2001. http://hub.hku.hk/bib/B31226619.

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42

張秀霞 e Sau-ha Cheung. "Growing of GaN on vicinal SiC surface by molecular beam epitaxy". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2002. http://hub.hku.hk/bib/B31243009.

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43

Shi, Min, e 施敏. "Growth of AlInN and zinc blende GaN by molecular beam epitaxy". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2007. http://hub.hku.hk/bib/B39558873.

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44

Clarke, S. "Growth and recovery kinetics during molecular beam epitaxy : a simulation study". Thesis, Imperial College London, 1988. http://hdl.handle.net/10044/1/47001.

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45

Knoll, Stephan Manuel. "Characterisation of ScN and ScGaN alloys grown by molecular beam epitaxy". Thesis, University of Cambridge, 2015. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.708504.

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46

Zhang, Yun. "High Quality ZnO Epitaxial Grown By Plasma Assisted Molecular Beam Epitaxy". VCU Scholars Compass, 2004. http://scholarscompass.vcu.edu/etd/883.

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Described in this thesis are the growth and characterization of high quality ZnO epitaxy layers.Zinc oxide (ZnO) epitaxy layers were grown on sapphire and epi-GaN substrates respectively, using plasma assisted molecular beam epitaxy (MBE) . Various growth conditions, such as growth temperature, II/VI ratio, and buffer layers, were employed to optimize the quality of the ZnO film. The subsequent characterization of the films was carried out to evaluate the surface, optical and crystalline properties of the film, using AFM, SEM, PL and XRD techniques. It was found out that the high quality of the ZnO film was grown on epi-GaN substrates under the Low temperature of ~ 300 degrees C, flash annealing up to ~680 degrees C, followed by high temperature growth at ~600 degrees C.

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47

Carrington, Peter James. "Quantum nanostructures grown by molecular beam epitaxy for mid-infrared applications". Thesis, Lancaster University, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.533092.

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48

Ozasa, Kazunari. "METALORGANIC MOLECULAR BEAM EPITAXY OF PHOSPHORUS-BASED III-V TERNARY SEMICONDUCTORS". Kyoto University, 1989. http://hdl.handle.net/2433/162234.

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49

Liu, Jian. "Molecular beam epitaxy growth of Si/Ge heterostructure for electron transport". Diss., Restricted to subscribing institutions, 2007. http://proquest.umi.com/pqdweb?did=1432804071&sid=1&Fmt=2&clientId=1564&RQT=309&VName=PQD.

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50

Smith, John Stephen Yariv Amnon. "III-V molecular beam epitaxy structures for electronic and optoelectronic applications /". Diss., Pasadena, Calif. : California Institute of Technology, 1986. http://resolver.caltech.edu/CaltechETD:etd-03082008-083912.

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