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Growth Mode (growth + mode)
Selected AbstractsAdvancing Firm Growth Research: A Focus on Growth Mode Instead of Growth RateENTREPRENEURSHIP THEORY AND PRACTICE, Issue 2 2010Alexander McKelvie The development of firm growth research has been notably slow. In this paper, we argue that a major reason for this lack of development is the impatience of researchers to prematurely address the question of "how much?" before adequately providing answers to the question "how?" On the basis of an extensive review of the literature, we suggest how growth research can advance by changing focus to growth mode (organic, acquisition, hybrid). Toward this end, we provide a research agenda that helps establish the types of questions that growth researchers can ask within this new focus. [source] Gate Dielectric Microstructural Control of Pentacene Film Growth Mode and Field-Effect Transistor Performance,ADVANCED MATERIALS, Issue 18 2007C. Kim Organic semiconductor/dielectric interfacial characteristics play a critical role in influencing organic thin-film transistor (OTFT) performance characteristics (see figure). Clear correlations between pentacene film deposition temperature, estimated polymer dielectric surface microstructural mobility, and the corresponding film growth mode, semiconductor phase composition, and carrier mobilities are established. [source] Random Deposition as a Growth Mode in Atomic Layer Deposition (Chem. Vap.CHEMICAL VAPOR DEPOSITION, Issue 5 2005Deposition 200 Abstract To view the original paper use http://dx.doi.org/10.1002/cvde.200306283. [source] Random Deposition as a Growth Mode in Atomic Layer Deposition,CHEMICAL VAPOR DEPOSITION, Issue 3 2004R.L. Puurunen Abstract Despite the increasing number of successful applications of material growth by atomic layer deposition (ALD), the description of many physicochemical processes that occur during ALD growth is still incomplete. The way the material is arranged on the surface during ALD growth, called the ALD growth mode, defines important material properties, such as when the substrate gets fully covered by the ALD-grown material, and the surface roughness. This work initiates the theoretical description of ALD growth modes by describing the random deposition growth mode, both qualitatively and quantitatively, by using the growth per cycle as a statistical quantity. [source] Modelling the combined effect of temperature, pH and aw on the growth rate of Monascus ruber, a heat-resistant fungus isolated from green table olivesJOURNAL OF APPLIED MICROBIOLOGY, Issue 1 2003E.Z. Panagou Abstract Aims: Growth modes predicting the effect of pH (3·5,5·0), NaCl (2,10%), i.e. aw (0·937,0·970) and temperature (20,40°C) on the colony growth rate of Monascus ruber, a fungus isolated from thermally-processed olives of the Conservolea variety, were developed on a solid culture medium. Methods and Results: Fungal growth was measured as colony diameter on a daily basis. The primary predictive model of Baranyi was used to fit the growth data and estimate the maximum specific growth rates. Combined secondary predictive models were developed and comparatively evaluated based on polynomial, Davey, gamma concept and Rosso equations. The data-set was fitted successfully in all models. However, models with biological interpretable parameters (gamma concept and Rosso equation) were highly rated compared with the polynomial equation and Davey model and gave realistic cardinal pHs, temperatures and aw. Conclusions: The combined effect of temperature, pH and aw on growth responses of M. ruber could be satisfactorily predicted under the current experimental conditions, and the models examined could serve as tools for this purpose. Significance and Impact of the Study: The results can be successfully employed by the industry to predict the extent of fungal growth on table olives. [source] Advancing Firm Growth Research: A Focus on Growth Mode Instead of Growth RateENTREPRENEURSHIP THEORY AND PRACTICE, Issue 2 2010Alexander McKelvie The development of firm growth research has been notably slow. In this paper, we argue that a major reason for this lack of development is the impatience of researchers to prematurely address the question of "how much?" before adequately providing answers to the question "how?" On the basis of an extensive review of the literature, we suggest how growth research can advance by changing focus to growth mode (organic, acquisition, hybrid). Toward this end, we provide a research agenda that helps establish the types of questions that growth researchers can ask within this new focus. [source] Effect of Contact Mode on the Electrical Transport and Field-Emission Performance of Individual Boron NanowiresADVANCED FUNCTIONAL MATERIALS, Issue 12 2010Fei Liu Abstract Vapor,liquid,solid processing of boron nanowires (BNWs) can be carried out either using a bottom-up or top-down growth mode, which results in different contact modes between the nanowire and the substrate. The contact mode may strongly affect the electrical transport and field-emission performance of the individual boron nanowires grown on a Si substrate. The electrical transport and field-emission characteristics of individual boron nanowires of different contact modes are investigated in situ using a scanning electron microscope. The contact barriers are very distinct for the different contact modes. Moreover, the transition from a "contact-limited" to a "bulk-limited" field-emission (FE) process is demonstrated in nanoemitters for the first time, and the proposed improved metal,insulator,vacuum (MIV) model may better illustrate the nonlinear behavior of the Fowler-Nordheim (FN) plots in these nanoscale systems. Individual BNWs with different contact modes have a discrepancy in their emission stability and vacuum breakdown characteristics though they have similar aspect ratios, which suggests that their electrical transport and field-emission performance are closely related to their contact mode. Boron nanowires grown in the base-up mode have better field-emission performances and are more beneficial than those grown in the top-down mode for various device applications. [source] A proteomic study of Escherichia coli O157:H7 NCTC 12900 cultivated in biofilm or in planktonic growth modeFEMS MICROBIOLOGY LETTERS, Issue 1 2002Frédéric Trémoulet Abstract Escherichia coli 0157:H7 biofilms were studied by a new method of cultivation in order to identify some of the proteins involved in the biofilm phenotype. A proteomic analysis of sessile or planktonic bacteria of the same age was carried out by two-dimensional electrophoresis, matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF-MS) and database searching. Comparison of two-dimensional gels showed clear differences between protein patterns of sessile and planktonic cells. Fourteen proteins increased in biofilms, whereas three decreased. From these 17 proteins, 10 were identified by MALDI-TOF-MS and could be classified into four categories according to their function: (1) general metabolism proteins (malate dehydrogenase, thiamine-phosphate pyrophosphorylase), (2) sugar and amino acid transporters (d -ribose-binding periplasmic protein, d -galactose-binding protein, YBEJ), (3) regulator proteins (DNA starvation protein and H-NS) and (4) three proteins with unknown function. The results of this study showed that E. coli O157:H7 modified the expression of several proteins involved in biofilm growth mode. [source] Pulsed Vapor-Liquid-Solid Growth of Antimony Selenide and Antimony Sulfide NanowiresADVANCED MATERIALS, Issue 31 2009Ren Bin Yang Antimony sulfide and antimony selenide nanowires are prepared in an original pulsed vapor-liquid-solid growth mode. The molecular precursors are not mixed together in the gas phase; therefore the chemical reaction forming the solid only occurs in the gold catalyst. The material is stoichiometric and highly crystalline. Wires consisting of Sb2S3 and Sb2Se3 segments can be obtained with the same process. [source] Gate Dielectric Microstructural Control of Pentacene Film Growth Mode and Field-Effect Transistor Performance,ADVANCED MATERIALS, Issue 18 2007C. Kim Organic semiconductor/dielectric interfacial characteristics play a critical role in influencing organic thin-film transistor (OTFT) performance characteristics (see figure). Clear correlations between pentacene film deposition temperature, estimated polymer dielectric surface microstructural mobility, and the corresponding film growth mode, semiconductor phase composition, and carrier mobilities are established. [source] Approaches for the coating of capillary columns with highly phenylated stationary phases for high-temperature GCJOURNAL OF SEPARATION SCIENCE, JSS, Issue 4 2004Bernhard X. Mayer-Helm Abstract Two highly phenylated tetramethyl- p -silphenylene,diphenylsiloxane copolymers were coated on fused silica capillary columns and used as stationary phases in GC. The copolymers offered new insights into the coating process and column preparation due to their physicochemical properties. The fused silica capillary surface had to be pretreated in various ways to achieve a homogeneous film and a well deactivated surface: etching with ammonium bifluoride; leaching with sodium hydroxide and hydrochloric acid; silylation with tetraphenyldimethyldisilazane and triphenylsilylamine. Droplet formation was observed on tetraphenyldimethyldisilazane silylated surfaces leading to capillary columns with low separation efficiency. The topology of inhomogeneous films was investigated by light microscopy, scanning electron microscopy, and Auger electron spectroscopy. It became apparent that the stationary phase did not form droplets but islands, which are connected by a wetting layer according to the Stranski-Krastanov growth mode. Both copolymers are potential stationary phases for high-temperature GC with promising properties. They offer a higher overall polarity than 75% phenyl, 25% methyl-polysiloxanes in combination with increased thermal stability and reduced bleed levels. [source] Structural and optical characterization of pulsed laser-ablated potassium lithium niobate thin filmsPHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 12 2009V. Jayasree Abstract Thin films of potassium lithium niobate (K3Li2Nb5O15: KLN) have been prepared on glass substrate, as a function of substrate temperature, using a pulsed laser-deposition (PLD) technique for the first time. Grazing-incidence X-ray diffraction (GIXRD) analysis suggests that KLN films can be grown successfully at a substrate temperature as low as 300,K. The anomalous behavior of the decline of crystalline structure with increase in substrate temperature is explained. The atomic force microscopic (AFM) and scanning electron microscopic (SEM) images show an agglomerated growth mode for the films deposited at a substrate temperature of 300,K and a decrease in grain size with increase in substrate temperature. The films deposited at higher substrate temperatures show ring-like structures. The AFM analysis shows that the rms surface roughness of the film decrease with increase in substrate temperature. The UV,Vis transmission spectra suggest that the nature of the transition in the films is directly allowed. A blue shift in optical bandgap is observed for the films compared to bulk material. The changes in the optical bandgap with substrate temperature are also discussed. [source] Application of microsize light-emitting diode structure for monolithic optoelectronic integrated circuitsPHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 6 2007S. Y. Moon Abstract A Si/III,V,N alloys/Si structure was grown on a Si substrate by solid-source molecular beam epitaxy (SSMBE) with an rf plasma nitrogen source and electron-beam (EB) evaporator. A two-dimensional (2D) growth mode was maintained during the growth of all layers. High-resolution X-ray diffraction (HRXRD) revealed that the structure had a small lattice mismatch to the Si substrate. InGaPN/GaPN double-heterostructure (DH) light-emitting diodes (LEDs) were fabricated on Si/III,V,N alloys/Si structure. The various sized LEDs were fabricated to put into the MOSFET for monolithic optoelectronic integrated circuits (OEIC). The luminescence properties of LEDs were evaluated by electroluminescence (EL). A double emission peak from all LED samples was observed at about 642 nm and 695 nm at room temperature (RT). As injection current increased, the emission peak wavelength changed from the peak wavelength of the InGaPN layer to that of the GaPN layer, likely due to carrier overflow of the active layer. A simplified fabrication process for the microsize LED of the unit circuit was proposed. The LEDs with emission areas from 5 × 5 ,m2 to 20 × 20 ,m2 were fabricated. The LED with an emission area of 5 × 5 ,m2 can be applied to an optical device of a monolithic OEIC. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Growth optimisation of the GaN layers and GaN/AlGaN heterojunctions on bulk GaN substrates using plasma-assisted molecular beam epitaxyPHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 2 2004C. Skierbiszewski Abstract Influence of growth conditions in plasma assisted molecular beam epitaxy on quality of GaN layers and GaN/AlGaN heterojunctions is studied. The growth diagram for step-flow growth mode and different nitrogen flux is presented. The low defect density of bulk GaN substrates together with very low impurity background concentrations resulted in high electron mobility for GaN/AlGaN heterojunctions: 109,000 cm2/Vs at 1.5 K, and 2500 cm2/Vs at 295 K. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] GaAs nanowires grown by MOVPEPHYSICA STATUS SOLIDI (B) BASIC SOLID STATE PHYSICS, Issue 6 2010Jens Bauer Abstract GaAs nanowire (NW) growth was studied by metal-organic vapour phase epitaxy (MOVPE). The vapour,liquid,solid (VLS) mechanism with gold-based alloy particles and the selective-area growth (SAG) mechanism on electron beam lithographically prepared SiNx/GaAs mask structures were applied. A special focus is set on thermodynamic aspects of the VLS process. The alloy particle formation and the influence of MOVPE growth parameters on the growth rate and the GaAs NW morphology are examined. Furthermore, the improvement of the real structure with particular interest on the twin formation is studied. Besides the commonly used continuous VLS growth mode also a pulsed VLS growth mode with alternating precursor supply is reported. Based on photoluminescence measurements the effect of strain in core/shell NW structures is confirmed. For the SAG mechanism the MOVPE growth parameters are determined and the real structure is described. [source] Surface morphology effects on the optical phonon modes in InAsxSb1,x epilayers on GaAs(001)PHYSICA STATUS SOLIDI (B) BASIC SOLID STATE PHYSICS, Issue 4 2006P. Jayavel Abstract We have studied Raman scattering from longitudinal- and transverse-optical (LO and TO) phonon modes in InAsxSb1,x epilayers grown on GaAs(001) substrates with various arsenic compositions (x). InSb-like and InAs-like LO and TO phonon modes of the epilayers are observed. We find that the peak intensity ratio of the InAs-like LO to TO-mode decreases for x < 0.6 while it increases for x > 0.6. This intensity ratio change is attributed to two- and three-dimensional (2D and 3D) growth mode of the epilayers using atomic force microscopy. Further, the intensity ratio depends on the root mean square surface roughness of the alloy. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] High-quality ZnO epilayers grown on Zn-polar ZnO substrates by plasma-assisted molecular beam epitaxyPHYSICA STATUS SOLIDI (B) BASIC SOLID STATE PHYSICS, Issue 3 2004Hiroyuki Kato Abstract High-quality ZnO epilayers have been grown on Zn-polar ZnO substrates by plasma-assisted molecular beam epitaxy. With increasing O/Zn flux ratio from the stoichiometric to the O-rich, the growth mode changed from three- to two-dimensional growth and the line widths of (0002) and (10,10) ,-rocking curves showed dramatic narrowing from 471 to 42 arsec and from 1635 to 46 arcsec, respectively. These values are narrower compared to those of ZnO on sapphire and also those of device-grade MOCVD-grown GaN. Moreover, A-, B-excitons (FEA, FEB), and the n = 2 state of FEA at 3.378, 3.393, and 3.424 eV, respectively, were clearly observed in the low-temperature (4.2 K) photoluminescence spectrum of ZnO grown under O-rich flux conditions. Our results show that growth under high O-rich flux conditions is required to produce high-quality Zn-polar ZnO films. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Stranski,Krastanow growth of stacked GaN quantum dots with intense photoluminescencePHYSICA STATUS SOLIDI (B) BASIC SOLID STATE PHYSICS, Issue 2 2003K. Hoshino Abstract Multiple-layer stacked GaN quantum dots (QDs) with intense photoluminescence (PL) have been grown by the Stranski,Krastanow growth mode in metalorganic chemical vapor deposition. Scanning transmission electron microscopy (STEM) analysis shows that the vertical aligned QDs are formed, which results from a strain field induced by buried islands. We have also investigated PL spectra at room temperature. The PL intensity increases with increasing number of the stacked layer. This indicates that the carriers can be injected into each layer of GaN quantum dots. (© 2003 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Improvement of crystal quality of GaN grown on AlN template by MOCVD using HT-AlN interlayerPHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue S2 2009Tao Yuebin Abstract Two GaN samples, with and without high temperature (HT)-AlN interlayer (labelled as sample A and B, respectively) grown by MOCVD on AlN template, were investigated by double-crystal X-ray diffraction (DC-XRD), photoluminescence (PL), and atomic force microscope (AFM) measurements. It was found that the crystal quality of GaN could be greatly improved by the HT-AlN interlayer. The full width at half maximum (FWHM) of (102) reflection in XRD rocking curve was narrower for sample A than that for sample B. However, the FWHMs of (002) reflections were almost the same for the two samples. In addition, the tilt degree which reflected screw dislocation density was almost the same, while the twist degree which reflected edge dislocation density changed from 0.214° to 0.152° when the HT-AlN interlayer was used. Both the intensities of (102) reflection in XRD and band edge emission in PL for sample A were stronger too. In the AFM images, the atomic growth steps of sample A were clearer than those of sample B. According to the results of the in situ optical reflectivity spectra and the atomic force microscope (AFM) images, the above results were attributed to the three-dimensional (3D) growth mode of the HT-AlN interlayer. The HT-AlN interlayer may work as a kind of "micro-area" seed for epitaxial lateral overgrowth (ELOG) resulting in bending some dislocations. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Pulsed layer growth of AlInGaN nanostructuresPHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 6 2008Michael Jetter Abstract A pulsed layer growth mode in the metal-organic vapor phase epitaxy (MOVPE) was used to fabricate excellent quality AlInGaN nanostructures. The amount of material was varied, resulting in AlInGaN layer thicknesses between nominally 1.5 nm and 6 nm, respectively. We have analyzed the material properties by X-ray diffraction (XRD) as well as photoluminescence (PL) spectroscopy. The observed XRD-spectra and the PL intensity show the high quality of the deposited material. By analyzing the PL spectra we have found an energetic shift of the resonance lines from 2.65 eV to 3.33 eV with decreasing well thickness. We attribute this shift mainly to the presence of internal electric fields at the AlIn-GaN/GaN interface. Power-dependent and time resolved PL experiments confirm this observation. Comparing the luminescence at elevated temperatures, the pulsed layer epitaxy structures reveal a much higher intensity as the conventional grown samples. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Direct MOVPE- and MBE-growth of a-plane GaN on r-plane sapphirePHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 6 2008T. Aschenbrenner Abstract We report on the growth of pit-free a-plane GaN on (102) sapphire (r-plane) substrates by metal organic vapor phase epitaxy (MOVPE) using a three step growth method without low temperature nucleation layer. X-ray diffraction , -scans of the symmetric GaN (11-20) reflex revealed for 1.2 ,m thick crack- and pit-free GaN layers low FWHM of 885 arcsec and 2484 arcsec measured by inclination in c- and m-direction, respectively. To analyze the evolution growth was stopped at different stages and the samples were measured with AFM, SEM, and XRD. Furthermore, we discuss the overgrowth of MOVPE GaN layer with molecular beam epitaxy (MBE). For smooth MOVPE templates with closed surfaces the morphology was reproduced, whereas for not coalesced thinner layers a different growth mode and a smoothening of the layers occurred. We will discuss SEM- and AFMdata in detail to examine this overgrowth procedure. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Mechanisms of bending of threading dislocations in MOVPE-grown GaN on (0001) sapphirePHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 6 2006R. Datta Abstract In this article, we describe possible mechanisms associated with the bending of threading dislocations (TDs) through 90° in GaN. In-situ ELOG using SiNx masking on a sapphire substrate and in-situ SiNx interlayer (IL) deposition on a GaN pseudo-substrate have been used to reduce the TD density in GaN. The bending of TDs through 90° is essential in order to reduce their numbers in the upper growing layer. The bending of TDs is facilitated by a change in growth mode, i.e. predominantly 2D to 3D and then 3D to 2D. A new mechanism is tentatively proposed which can explain the bending of all types of TDs (edge, screw, and mixed). This new mechanism is based on first, step formation at 3D island side facets when TDs terminate there, following which, depending on the subsequent change in growth mode (3D to 2D) and the direction of the atomic ledge movement, the TDs will bend over. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Ultra-flat and high-quality AlN thin films on sapphire (0001) substrates grown by rf-MBEPHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 7 2003X. Q. Shen Abstract AlN films on sapphire (0001) substrates grown by plasma-assisted molecular beam epitaxy are investigated. In-situ reflection high-energy electron diffraction shows a streak pattern from the beginning of the AlN growth indicating the 2-dimensional (2D) growth mode of AlN. High-resolution X-ray diffraction measurements illustrate that the full-width at half maximum of AlN (0002) peak is less than 80 arcsec when the thickness of AlN is more than 200 nm showing high structural film quality. Clear near-band edge emission at 77 K is observed from an 800 nm-thick AlN film by cathodoluminescence measurements. Atomic force microscopy observations show ultra-flat surface morphologies of AlN with rms as small as 0.12 nm. All characterization results suggest the high-quality of AlN films. (© 2003 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Formation and optical properties of Cr-doped CdTe/ZnTe nanostructures on ZnTe substrates by molecular beam epitaxyPHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 4 2003K. Godo Abstract We study the growth and optical properties of Cr-doped CdTe/ZnTe nanostructures grown on ZnTe (001) substrates by molecular beam epitaxy. In-situ reflection high-energy electron diffraction is used to study the growth processes and strain relaxation behaviors of Cr-doped CdTe quantum dots (QDs). After 4.5,ML deposition, the surface lattice parameter begins to increase remarkably, which indicates that the two-dimensional growth mode is terminated and the CdTe layer grows in a three-dimensional mode. Low temperature photoluminescence spectra of Cr-doped CdTe QDs (Tcr = 900 °C) show a broad emision. With increasing the Cr cell temperature above 1000 °C, the luminescence from CdTe QDs disappears and the broad luminescence at around 1.6 eV becomes dominant. [source] High quality InAs quantum dots covered by InGaAs/GaAs hetero-capping layerPHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 3 2003R. Ohtsubo Abstract Self-assembled InAs quantum dots with high performance were fabricated by molecular beam epitaxy via Stranski,Krastanov growth mode and InGaAs/GaAs hetero-capping growth. The size and shape of the dots were modified during the first GaAs capping layer, which plays an important role of a reduction in the inhomogeneous broadening. In particular, when the substrate temperature of the GaAs capping layer was 450,°C, the PL linewidth decreased to less than 20,meV. In order to reduce the residual strain in the InAs QDs and the capping layer, the InGaAs capping layer was additionally grown on the InAs dots covered by the first GaAs capping layer. As a result, the presented InGaAs/GaAs hetero-capping layer induced strong photoluminescence (PL) intensity, narrow PL linewidth and 1.3,,m light emission at room temperature. [source] Repeated Growing and Annealing Towards ZnO Film by Metal-Organic CVD,CHEMICAL VAPOR DEPOSITION, Issue 7-9 2009Chia-Cheng Wu Abstract ZnO deposited on sapphire substrate is investigated as a function of growth temperature in the range 350,650,°C. The surface morphology of ZnO structures changes significantly with increasing growth temperature. Though ZnO crystal quality and optical property can be improved under high growth temperature, ZnO is inclined to form nanostructures. Therefore, we propose the repeated growing and annealing (RGA) growth mode as a reliable and reproducible way for the growth of ZnO film. The RGA growth mode is performed at a growth temperature of 450,°C for 8,min, an anneal temperature of 650,°C for 20,min, and repeatedly switched between growing and annealing. Meanwhile, we compare the effects of annealing under Ar, N2, and O2, and found that a low resistivity of 3.4,×,10,3,, cm and a high mobility of 85.2,cm2 V,1 s,1 can be obtained annealing under N2. [source] Random Deposition as a Growth Mode in Atomic Layer Deposition,CHEMICAL VAPOR DEPOSITION, Issue 3 2004R.L. Puurunen Abstract Despite the increasing number of successful applications of material growth by atomic layer deposition (ALD), the description of many physicochemical processes that occur during ALD growth is still incomplete. The way the material is arranged on the surface during ALD growth, called the ALD growth mode, defines important material properties, such as when the substrate gets fully covered by the ALD-grown material, and the surface roughness. This work initiates the theoretical description of ALD growth modes by describing the random deposition growth mode, both qualitatively and quantitatively, by using the growth per cycle as a statistical quantity. [source] Time evolution of cholesteric fingers of the second species in an electric fieldCRYSTAL RESEARCH AND TECHNOLOGY, Issue 12 2009S. Pirkl Abstract Different growth modes of isolated cholesteric fingers of the second species (CF-2) in an electric field at voltages near a coexistence line (V2) between cholesteric and nematic mesophases are in detail described. Videomicroscopy and computer image analysis were used for investigation of the pattern in polarized light. It is shown how a drift, a lengthening and a shape of fingers depend on the voltage at which the growth sets in and three typical scenarios are distinguished. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] ZnO nanowire arrays , Pattern generation, growth and applicationsPHYSICA STATUS SOLIDI (B) BASIC SOLID STATE PHYSICS, Issue 10 2010Margit Zacharias Abstract ZnO nanowires and related materials are in the focus of attention for electronic, optical or sensor applications. However, size, position and arrangement control are essential conditions for the development of future nanowire based devices. Various kinds of template methods including nanosphere lithography and UV laser interference lithography are powerful tools for the preparation of the starting metal catalyst arrays and will be demonstrated and discussed. However, only if the growth mechanism and its guiding parameters are understood in detail, the template will force a pattern arranged growth of nanowires. The paper gives an overview of the various kinds of growth modes for vertical arranged nanowires. Specific experimental conditions establishing the VS or the VLS growth are discussed. In addition, insight is given why the patterning is not all the time conserved and how to overcome these obstacles. In the second part different kinds of applications are summarized. Electronic properties are discussed based on metal,semiconductor,metal devices. The influence of a core,shell nanowire structure on the optical properties is demonstrated. In addition, a simple approach for ZnO nanowire based gas sensors is discussed and shown. As a last example, the transfer of Al2O3 coated nanowires into spinel tubes is reported. [source] Trichloroethene and cis -1,2-dichloroethene concentration-dependent toxicity model simulates anaerobic dechlorination at high concentrations.BIOTECHNOLOGY & BIOENGINEERING, Issue 3 2010II: Continuous flow, attached growth reactors Abstract A model that was used to describe toxicity from high concentrations of chlorinated aliphatic hydrocarbons (CAHs) on reductively dechlorinating cultures in batch reactors (Sabalowsky and Semprini (in press)) was extended here to simulate observations in continuous flow suspended and attached growth reactors. The reductively dechlorinating anaerobic Evanite subculture (EV-cDCE) was fed trichloroethene (TCE) and excess electron donor to accumulate cis -1,2-dichloroethene (cDCE) in a continuous flow stirred tank reactor (CFSTR); and an attached growth recirculating packed column (RPC). A concentration-dependent toxicity model used to simulate the results of batch reactors in part I (Sabalowsky and Semprini (in press) Biotechnol Bioeng) also simulated well the observations for the CFSTR and RPC growth modes. The toxicity model incorporates cDCE and TCE toxicity coefficients that directly increase the cell decay coefficient in proportion with cDCE and TCE concentrations. Simulated estimates of the cDCE and TCE toxicity coefficients indicate reductively dechlorinating cells are most sensitive to high concentrations of cDCE and TCE in batch-fed growth, followed by CFSTR, with attached growth being least sensitive. The greater toxicity of TCE than cDCE, and ratio of the modeled toxicity coefficients, agrees with previously proposed models relating toxicity to partitioning in the cell wall (KM/B), proportional to octanol-water partitioning (KOW) coefficients. Biotechnol. Bioeng. 2010;107: 540,549. © 2010 Wiley Periodicals, Inc. [source] | |||||||||||||||||||