Les fibres à base de nanotubes de carbone (NTC), de par leurs propriétés électriques et mécaniques, sont des candidates potentielles pour des applications telles que les textiles fonctionnels ou les câbles conducteurs. A ce jour, deux familles de fibres, préparées selon des voies différentes, coexistent : les fibres contenant seulement des NTC et les fibres composites polymère/NTC. Les caractéristiques des NTC et les voies de mise en forme sont des facteurs reconnus pour impacter les propriétés électriques et mécaniques des fibres. Toutefois, compte tenu de la variabilité des sources de NTC et des conditions d’élaboration, il est difficile de dégager des relations entre caractéristiques des fibres et propriétés. C’est dans ce contexte que se situent ces travaux, avec comme objectifs la préparation de fibres à partir de NTC verticalement alignés selon deux voies d’élaboration et l’étude de leurs propriétés en fonction des caractéristiques des NTC. Une première partie de l’étude s’est focalisée sur la faisabilité de filage (voie sèche) à partir de tapis de NTC synthétisés par CCVD d’aérosol afin d’obtenir des fibres composée seulement de NTC. Même si l’ensemble des essais n’a pas abouti à un filage continu, ils ont permis de mettre en évidence un lien entre la faible tortuosité des NTC au sein du tapis et la capacité de ce dernier à former un réseau cotonneux qui semble être nécessaire à l’obtention d’une fibre. La seconde partie concerne l’étude de l’effet des caractéristiques des NTC (longueur, diamètre et structure) sur les propriétés électriques et mécaniques de fibres composites NTC/alcool polyvinylique (PVA) obtenues par voie humide à partir de suspensions de NTC. Or, la préparation de ces dernières engendre une rupture des NTC dont la longueur en suspension est limitée au micromètre. Un nouveau procédé de dispersion basé sur l’utilisation de cycles de gel/dégel a été développé, permettant d’aboutir à des longueurs de NTC en suspension de l’ordre de 4 à 6 µm. Ainsi, des suspensions concentrées en NTC de longueur, structure et diamètre différents ont été obtenues et ont permis d’élaborer avec succès des fibres composites. Les propriétés mécaniques des fibres brutes sont essentiellement modifiées par la longueur des NTC qui conduit à une amélioration du module de Young et de la contrainte à la rupture. Les propriétés électriques dépendent de la concentration en NTC dans la fibre et de la structure des NTC. Après traitement des fibres à 200 °C, l’augmentation de la longueur des NTC entraine une amélioration de la conductivité électrique. Par conséquent, l’utilisation de NTC longs dans des fibres composites s’avère bénéfique en termes d’augmentation des performances. / Carbon nanotube (CNT) based fibers, due to their interesting electrical and mechanical properties, exhibit a broad range of potential applications, such as functional textile or electrical wiring. To date, there are two families of fibers prepared according to different routes: pure CNT fibers and CNT composite fibers. The CNT characteristics and the elaboration process are known to impact their electrical and mechanical properties. However, the large diversity of manufactured CNT and spinning conditions used to elaborate these fibers are not favorable to establish clear relationship between fiber characteristics and their properties. In this context, the aim of the present work is to prepare fibers from vertically aligned CNT carpet according to two different elaboration process and to study their properties according to the CNT characteristics. A first part of this study was focused on the dry-spinning feasibility directly from CNT carpet synthesized by aerosol-assisted CCVD process in order to prepare fibers containing only of CNT. Even though all tests did not lead to a continuous spinning, a relation between the weak CNT tortuosity and the capacity of carpet to form fluffy network was established, which seems important for fiber continuous spinning. The second part is devoted to the study of the CNT characteristic effect (length, diameter and structure) on the electrical and mechanical properties of composite fibers obtained by wet spinning from CNT suspension. However, the preparation of these suspensions generates a CNT breakage by reducing their length to the micrometer range. A new dispersion process based on freezing/thawing cycles was developed and enables to keep CNT length in suspension of about 4 to 6 µm. Thus, concentrated suspensions with different CNT length, structure and diameter were obtained and successfully spun into fibers. The mechanical properties of raw fibers are essentially modified by CNT length which involves an improvement of the Young modulus and the tensile strength. The electrical properties depend on the CNT concentration in fiber and on the CNT structure. After a heat treatment of fiber at 200 °C, the increase of CNT length leads to an improvement of electrical conductivity. Consequently, the use of long CNT in composite fibers is beneficial to improve their performances.

Carbon nanotubes (CNTs) have become a popular area of materials science research due to their outstanding material properties coupled with their small size. CNTs are expected to be included in a wide variety of applications and devices in the near future. Among these devices which are nearing mass production are electrochemical double layer (ECDL) supercapacitors. The current methods to produce CNTs are numerous, with each synthesis variable resulting in changes in the physical properties of the CNT. A wide array of studies have focused on the effects of specific synthesis conditions. This research expands on earlier work done using bulk nickel catalyst, alumina supported iron catalyst, and standard chemical vapor deposition (CVD) synthesis methods. This work also investigates the effect of an applied voltage to the CVD chamber during synthesis on the physical nature of the CNTs produced. In addition, the work analyzes a novel nickel catalyst system, and the CNTs produced using this catalyst. The results of the effects of synthesis conditions on resultant CNTs are included. Additionally, CNT based ECDL supercapacitors were manufactured and tested. Scanning electron microscope (SEM) analysis reveals that catalyst choice, catalyst thickness, synthesis temperature, and applied voltage have different results on CNT dimensions. Nanotube diameter distribution and average diameter data demonstrate the effect of each synthesis condition. Additionally, the concept of an alignment parameter is introduced in order to quantify the effect of an electric field on CNT alignment. CNT based ECDL supercapacitors testing reveals that CNTs work well as an active material when a higher purity is achieved. The molarity of the electrolyte also has an effect on the performance of CNT based ECDL supercapacitors. On the basis of this research, we conclude that CNT physical dimensions can be moderately controlled based on the choice of synthesis conditions. Also, the novel nickel catalyst system investigated in this research has potential to produce bulk quantities of CNT under specific conditions. Finally, purified CNTs are recommended as a suitable active material for ECDL supercapacitors.

[Truncated abstract] This study investigates the thermal stability of Plasma Enhanced Chemical Vapor Deposited (PECVD) silicon nitride thin films. Effects of heat-treatment in air on the chemical composition, atomic bonding structure, crystallinity, mechanical properties, morphological and physical integrity are investigated. The chemical composition, bonding structures and crystallinity are studied by means of X-ray Photoelectron Spectroscopy (XPS), Fourier Transform Infrared (FTIR) Spectroscopy and Transmission Electron Microscopy (TEM). The mechanical properties, such as hardness and Young’s modulus, are determined by means of nanoindentation. The morphological and physical integrity are analyzed using Scanning Electron Microscopy (SEM) . . . The Young’s modulus (E) and hardness (H) of the film deposited at 448 K were measured to have E=121±1.8 GPa and H=11.7±0.25 GPa. The film deposited at 573 K has E=150±3.6 GPa and H=14.7±0.6 GPa. For the film deposited at 573 K, the Young’s modulus is not affected by heating up to 1148 K. Heating at 1373 K caused significant increase in Young’s modulus to 180∼199 GPa. This is attributed to the crystallization of the film. For the film deposited at 448 K, the Young’s modulus showed a moderate increase, by ∼10%, after heating to above 673 K. This is consistent with the much lower level of crystallization in this film as compared to the film deposited at 573 K. In summary, low temperature deposited PECVD SiNx films are chemically and structurally unstable when heated in air to above 673 K. The main changes include oxidation to SiO2, crystallization of Si3N4 and physical cracking. The film deposited at 573 K is more stable and damage and oxidation resistant than the film deposited at 448 K.

There has been progress in the surface modification of low carbon steel in order to enhance its surface hardness. This study contributes to this by investigating the introduction of carbon nanotubes and amorphous carbon in the carburization of mild steel. In order to achieve the goal, carbon nanotubes were synthesized in a horizontal tubular reactor placed in a furnace also called the chemical vapor deposition process at a temperature of 700oC. Catalyst was produced from Iron nitrate Fe(NO3)3.9H2O and Cobalt nitrate Co(NO3)2.6H2O on CaCO3 support while acetylene C2H2 was used as the carbon source and nitrogen N2 was used as contaminant remover. The as-synthesized carbon nanotubes were purified using nitric acid HNO3 and characterized using scanning electron microscopy (SEM), thermo-gravimetric analysis (TGA) and fourier transform infrared spectroscopy (FTIR). It was found that as-synthesized carbon nanotubes had varying lengths with diameters between 42-52 nm from the SEM and the TGA showed the as-synthesized CNTs with a mass loss of 78% while purified CNTs had 85% with no damage done to the structures after using the one step acid treatment. The as-synthesized and purified carbon nanotubes were used in carburizing low carbon steel (AISI 1018) at two austenitic temperatures of 750oC and 800oC and varying periods of 10-50 minutes while amorphous carbon obtained by pulverizing coal was also used as comparison. The mild steel samples were carburized with carbon nanotubes and amorphous carbon in a laboratory muffle furnace with a defined number of boost and diffusion steps. The carburizing atmosphere consisted of heating up to the varying temperatures at a speed of 10oC/minute, heating under this condition at varying periods, performing a defined number of boost and diffusion processes at the varying temperatures and cooling to room temperatures under the same condition. The carburized surfaces were observed with the Olympus SC50 optical microscope and the hardness distribution of the carburized layer was inspected with a Vickers FM 700 micro-hardness tester. The as-synthesized and purified CNT samples showed higher hardness on the surface of the mild steel than the amorphous carbon. In the same vein, the change in the microstructures of vi the steel samples indicated that good and improved surface hardness was obtained in this work with the reinforcements but with purified CNT having the highest peak surface hardness value of 191.64 ± 4.16 GPa at 800oC, as-synthesized CNT with 177.88 ± 2.35 GPa and amorphous carbon with 160.702 ± 5.79 GPa which are higher compared to the values obtained at 750oC and that of the original substrate which had a surface hardness of 145.188 ± 2.66 GPa. The percentage hardness obtained for the reinforcement with the amorphous carbon, the CNT and the pCNT showed an increase of 5.47%, 10.04% and 15.77% respectively at 750oC when compared to that of the normal substrate carburized without reinforcements. Furthermore, at 800oC, the reinforcement with the amorphous carbon, the CNT and the pCNT show a percentage hardness increase of 7.04%, 14.68% and 22.05% when compared to that of the normal substrate carburized without reinforcements. Comparing the reinforcement potential of the amorphous carbon, the CNT and the pCNT at 750oC, the percentage hardness reveal that using pCNT displayed an increase of 10.89% over that of amorphous carbon and of 6.37% over that of CNT. In addition, the use of CNT as reinforcement at 750oC displayed a percentage hardness increase of 4.83% over that of the amorphous carbon carburized at the same temperature / Civil and Chemical Engineering / M. Tech. (Chemical Engineering)

The work carried out as a part of this thesis has been focussed on understanding different aspects of the chemical vapor deposition process namely, ALD / MOCVD. A large part of the thesis is aimed at solving the problem of a single-source precursor for the MOCVD process to obtain substituted metal oxide thin films. For a chemical vapor deposition technique, it is important to understand the requisite salient features of precursor for deposition of thin films. For this purpose, not only is the structural characterization of the chemical precursor is required but also an in-depth thermal analysis of the precursor to know its vapor pressure. Vapor pressure of a metalorganic complex is one of the important properties to evaluate the applicability of a metalorganic complex as a MOCV/ALD precursor. The thesis discusses a novel approach to use thermal analysis as a tool to gauge the viability of substituted metal “single source” precursor for MOCVD/ALD. The other half deals with material characterization of thin films grown by an ALD process using hydrogen and Ti(OiPr)2(tbob)2 as precursors. The films were further studied for their potential application as high-k dielectric in DRAM applications. The first chapter is an overview of topics that are relevant to the work carried out in this thesis. The chapter focuses on the description of techniques used for thin film deposition. A detailed review of CVD-type techniques (ALD/ MOCVD) is then given. Chapter1 reviews the various process parameters involved in ALD,i.e. film growth(specifically as a function of the reactant pulse length, the nature of the chemical reactant/precursor and that of the metal precursor, and purge length) and growth temperature. Following the discussion of ALD, CVD and its growth kinetics are also discussed. Chapter 1 then outlines a holistic understanding of precursors, followed the differences in requirement for using them in ALD and MOCVD. Further, an introduction to the titanium oxide (Stoichiometric titanium dioxide and various Magneli phases) system, its phase diagram, oxide properties and their applications is given. Chapter 1 concludes by delineating the scope of the work carried out which is presented in the thesis. The second chapter deals with the synthesis of a series of substituted metal “single source” precursors to be used for MOCVD of substituted metal oxides thin films. The precursor complexes were of the type AlxCr1-x (acac)3 where 0<x<1. The complexes were synthesized using the novel approach of co-synthesis and were characterized by various spectroscopic techniques. Single crystal X-ray diffraction at low temperature was carried out to understand the substitution of metal in the complex crystallographically. The substituted metal complexes synthesized and characterized in chapter 2 were further evaluated for their viability as single source precursors for MOCVD application, using thermo-gravimetry as discussed in chapter 3. Vapor pressure of these complexes was determined by using the Langmuir equation, while the enthalpies of submission and evaporation were calculated using the Clausius-Clapeyron equation. One of the composition of the series of substituted metal complexes, viz., Al0.9Cr0.1(acac)3, was employed on MOCVD reactor as precursor to obtain thin films on three substrates, Si(100), fused silica, and polycrystalline x- alumina, simultaneously. The resultant thin films were characterized using XRD, electron microscopy, FTIR, EDS, X-ray mapping, and UV-vis spectroscopy. Chapter 4 deals with the growth of titanium oxide thin films using ALD. The metal precursor used was Ti(OiPr)2(tbob)2 and the reactant gas was hydrogen. Hydrogen, a reducing gas, was deliberately used to obtain the reduced defect oxide phases of titanium, commonly called Magneli phases. The growth rate of films grown on p-Si(100) was studied with respect to the substrate temperature, vaporizer temperature, pulse duration of metal precursor and pulse duration of the reactive gas. Also, the concept of complementarity of a reaction and self-limiting behavior in a true ALD process was illustrated. The deposition conditions such as substrate temperature and reactive gas flows have been varied to optimize the phase content and the morphology of the films. The films grown were characterized to determine the various phases of titanium oxide present using XRD, TEM, FTIR spectroscopy, Raman spectroscopy, and UV-vis spectroscopy. The presence of carbon was revealed by Raman spectroscopy. By using these characterization techniques, it was concluded that the film grown is a composite made of stiochiometric TiOx matrix embedded with crystallites of (reduced) Magneli phases. Chapter 5 deals with the electrical properties of the composite thin films grown in chapter 4. the films behave as percolative capacitor which could be used for application as novel high-k dielectric material for DRAM. The effect of change in flow rates of reactive gas (H2) on the dielectric constant (k) and leakage current of the film were studied. It was found that phase composition of the film plays an important role in tuning the dielectric properties of the film was also studied. The effect of thickness of the film also studied on the dielectric properties of the film. The trend observed was correlated to the morphology of the film as a function of its thickness and the grain growth mechanism as observed from high resolution scanning electron microscopy. Further, the effect of change in substrate temperature, metal precursor pulse length, and of the metal used as top electrode, on C-V and I-V characteristics were studied. It was interesting to see that the presence of the more conductingTi5O9 (than Ti3O5) enhances the dielectric constant, which is a requisite for a high-k material for DRAM application. On the other hand, the presence of Ti5O9 also increased the leakage current in the film, which was not desirable. It therefore suggested itself that an optimum embedment of Ti5O9 in the composite helps in enhancing the dielectric constant, while maintaining a low leakage current. Under optimum conditions, a dielectric constant of 210 at 1MHz was measured with a leakage current of 17 nA. The effect of the presence of carbon in the film was studied using Raman Spectroscopy, and it was found that a high leakage was associated with films having greater carbon content. In this chapter, electrical properties of composite thin films were also compared with those of stoichiometric titanium dioxide (a known dielectric). Further, a multilayer sandwich structure was proposed, such that it had a 53 mm thick stoichiometric TiO2 layer followed by 336nm thick composite film and again a 53nm thick stoichiometric titanium dioxide layer. The dielectric characteristics of this structure were found to be better than those of either of the other two.viz., stoichiometric titanium dioxide film or the composite thin film of titanium oxide.

Doctor of Philosophy / Department of Physics / Hongxing Jiang / InGaN based, blue and green light emitting diodes (LEDs) have been successfully produced over the past decade. But the progress of these LEDs is often limited by the fundamental problems of InGaN such as differences in lattice constants, thermal expansion coefficients and physical properties between InN and GaN. This difficulty could be addressed by studying pure InN and In[subscript]xGa[subscript]1-xN alloys. In this context Ga-rich In[subscript]xGa[subscript]1-xN (x≤ 0.4) epilayers were grown by metal organic chemical vapor deposition (MOCVD). X-ray diffraction (XRD) measurements showed In[subscript]xGa[subscript]1-xN films with x= 0.37 had single phase. Phase separation occurred for x ~ 0.4. To understand the issue of phase separation in Ga-rich In[subscript]xGa[subscript]1-xN, studies on growth of pure InN and In-rich In[subscript]xGa[subscript]1-xN alloys were carried out. InN and In-rich In[subscript]xGa[subscript]1-xN (x~0.97- 0.40) epilayers were grown on AlN/Al[subscript]2O[subscript]3 templates. A Hall mobility of 1400 cm[superscript]2/Vs with a carrier concentration of 7x1018cm[superscript]-3 was observed for InN epilayers grown on AlN templates. Photoluminescence (PL)emission spectra revealed a band to band emission peak at ~0.75 eV for InN. This peak shifted to 1.15 eV when In content was varied from 1.0 to 0.63 in In-rich In[subscript]xGa[subscript]1-xN epilayers. After growth parameter optimization of In- rich In[subscript]xGa[subscript]1-xN alloys with (x= 0.97-0.40) were successfully grown without phase separation. Effects of Mg doping on the PL properties of InN epilayers grown on GaN/Al[subscript]2O[subscript]3 templates were investigated. An emission line at ~ 0.76 eV, which was absent in undoped InN epilayers and was about 60 meV below the band edge emission peak at ~ 0.82 eV, was observed to be the dominant emission in Mg-doped InN epilayers. PL peak position and the temperature dependent emission intensity corroborated each other and suggested that Mg acceptor level in InN is about 60 meV above the valance band maximum. Strain effects on the emission properties of InGaN/GaN multiple quantum wells (MQWs) were studied using a single blue LED wafer possessing a continuous variation in compressive strain. EL emission peak position of LEDs varies linearly with the biaxial strain; a coefficient of 19 meV/GPa, characterizes the relationship between the band gap energy and biaxial stress of In[subscript]0.2Ga[subscript]0.8N/GaN MQWs.

Heteroepitaxial SiGe(C) layers have attracted immense attention as a material for performance boost in state of the art electronic devices during recent years. Alloying silicon with germanium and carbon add exclusive opportunities for strain and bandgap engineering. This work presents details of epitaxial growth using chemical vapor deposition (CVD), material characterization and integration of SiGeC layers in MOS devices. Non-selective and selective epitaxial growth of Si1-x-yGexCy (0≤x≤0.30, 0≤y≤0.02) layers have been performed and optimized aimed for various metal oxide semiconductor field effect transistor (MOSFET) applications. A comprehensive experimental study was performed to investigate the growth of SiGeC layers. The incorporation of C into the SiGe matrix was shown to be strongly sensitive to the growth parameters. As a consequence, a much smaller epitaxial process window compared to SiGe epitaxy was obtained. Incorporation of high boron concentrations (up to 1×1021 atoms/cm3) in SiGe layers aimed for recessed and/or elevated source/drain (S/D) junctions in pMOSFETs was also studied. HCl was used as Si etchant in the CVD reactor to create the recesses which was followed (in a single run) by selective epitaxy of B-doped SiGe. The issue of pattern dependency behavior of selective epitaxial growth was studied in detail. It was shown that a complete removal of pattern dependency in selective SiGe growth using reduced pressure CVD is not likely. However, it was shown that the pattern dependency can be predicted since it is highly dependent on the local Si coverage of the substrate. The pattern dependency was most sensitive for Si coverage in the range 1-10%. In this range drastic changes in growth rate and composition was observed. The pattern dependency was explained by gas depletion inside the low velocity boundary layer. Ni silicide is commonly used to reduce access resistance in S/D and gate areas of MOSFET devices. Therefore, the effect of carbon and germanium on the formation of NiSiGe(C) was studied. An improved thermal stability of Ni silicide was obtained when C is present in the SiGe layer. Integration of SiGe(C) layers in various MOSFET devices was performed. In order to perform a relevant device research the dimensions of the investigated devices have to be in-line with the current technology nodes. A robust spacer gate technology was developed which enabled stable processing of transistors with gate lengths down to 45 nm. SiGe(C) channels in ultra thin body (UTB) silicon on insulator (SOI) MOSFETs, with excellent performance down to 100 nm gate length was demonstrated. The integration of C in the channel of a MOSFET is interesting for future generations of ultra scaled devices where issues such as short channel effects (SCE), temperature budget, dopant diffusion and mobility will be extremely critical. A clear performance enhancement was obtained for both SiGe and SiGeC channels, which point out the potential of SiGe or SiGeC materials for UTB SOI devices. Biaxially strained-Si (sSi) on SiGe virtual substrates (VS) as mobility boosters in nMOSFETs with gate length down to 80 nm was demonstrated. This concept was thoroughly investigated in terms of performance and leakage of the devices. In-situ doping of the relaxed SiGe was shown to be superior over implantation to suppress the junction leakage. A high channel doping could effectively suppress the source to drain leakage. / <p>QC 20100715</p>

A small-scale model of a CVD reactor was built. Axial and radial of major species concentrations and temperature profiles were obtained with a micro gas chromatograph and a fine thermocouple. Those temperature and species concentrations revealed detailed thermal and chemical structures of the CVD reactor. The concentrations of argon plus hydrogen, methane, and C2Hx (C2H2 + C2H4 + C2H6) resulting from xylene decomposition were measured along the CVD at different temperatures. Ferrocene was added to xylene to investigate the effect of a catalyst on composition profiles. The results with ferrocene indicated an increase in CH4 and C2Hx concentrations. At 1000 C and above, the increase of C2Hx concentration is higher than that for CH4. The effect of ferrocene was very minor on the concentration of the gases. Finally composition and temperature profiles were measured and plotted for the radial direction at X=75 cm and T=1200 C. The overall rate constant for the gas-phase reaction was calculated based on the measured species concentration data using the Benson and Shaw reaction mechanism. Our study showed that the Benson and Shaw mechanism could be used in the temperature range lower than 800 C. Also the effect of hydrogen in the syntheses of CNTs, in the CVD reactor using xylene and ferrocene, was studied. Both single-step and two-step methods were applied. In the single-step method, the ferrocene was dissolved in the xylene. In the two step-method the catalyst preparation step was performed first; ferrocene powder was placed in the preheater for a certain period of time and carried by a mixture of argon and hydrogen at fixed concentration to get catalyst nanoparticles deposited on the reactor wall. Xylene then was injected to the reactor. To study the effect of hydrogen, the synthesized materials were observed by SEM and TEM. The results showed that the presence of hydrogen is essential for CNTs to be synthesized by the CVD method, and also the concentration of hydrogen in the reactor has a great effect on the quality of CNTs. The yield of CNTs in the two-step method was slightly higher than that in the one-step method.

Thin films are an enabling technology for a wide range of applications, from microprocessors to diffusion barriers. Nanolaminate thin films combine two (or more) materials in a layered structure to achieve performance that neither film could provide on its own. Atomic layer deposition (ALD) is a chemical vapor deposition technique in which film growth occurs through self limiting surface reactions. The atomic scale control of ALD is well suited for producing nanolaminate thin films. In this thesis, ALD of two nanolaminate systems will be investigated: Al₂O₃-Ta₂O₅ and ZnO-SnO₂. Al₂O₃ and Ta₂O₅ are high κ dielectrics that find application as gate oxides for field effect devices such as metal oxide semiconductor field effect transistors and thin film transistors. Al₂O₃-Ta₂O₅ nanolaminate films of a fixed composition and total thickness, but with varied laminate structures, were produced to explore the influence of layer thickness on dielectric behavior. Layer thickness was found to have little impact on the dielectric constant but a strong impact on the leakage current. Thick layered nanolaminates (with 2.5 to 10 nm layers) performed better than either pure material. Showing structure provides a means of tailoring nanolaminate properties. ZnSnO is an amorphous oxide semiconductor used to make transparent TFTs. Although ALD is naturally suited to the production of nanolaminates, the deposition of homogenous ternary compounds is still uncommon. For very thin depositions, nucleation behavior can dominate, resulting in ALD growth rates different than for thicker films. Initial work on ALD of the ZnO-SnO₂ system is presented, focusing on nucleation and growth of each material on the other. It was found that both ZnO and SnO₂ inhibit the growth of one another and a method was developed to characterize the average growth rate for few cycle depositions. / Graduation date: 2011

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