The methylene blue--semiconductor nanocrystals system was studied by absorption and fluorescence correlation spectroscopy, as well as integrated and time-resolved photoluminescence measurements. These studies point to the adsorption of methylene blue molecules on NC surface, with partial dimerization of the dye. Quantum dot luminescence quenching was observed with increasing dye concentration. Examination of band offsets for this system and lifetime measurements suggest that efficient charge transfer is responsible for the quenching. Surface functionalization of nanocrystals may reduce the extent of dye dimerization, thereby improving the charge transfer between CdTe nanocrystals and methylene blue. [DOI: 10.1380/ejssnt.2009.349]

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Single crystalline ZnO disk-like structure with good luminescent properties was obtained by a low temperature solution based method. Micro-emulsion was employed to assist the shape control. The product has a perfect hexagonal shape with flat bottom and up surfaces, and has a wide size distribution, the size ranges from nano to micro-scale. Electron diffraction (ED) pattern coupled with transmission electron microscopy (TEM) indicate that the single disk was single-crystalline. In cathodoluminescence (CL) studies at room temperature for wavelengths between 350 and 675 nm, we have observed a single exciton peak around 390 nm without any deep-level emission. The monochromatic CL mapping in the ultra-violet (UV) region has such properties as: the intensity is concentrated along the boundary of the cavity; the emission is predominantly at the corner. [DOI: 10.1380/ejssnt.2009.354]

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ZnO tower-like structures with hexagonal cross section were fabricated by a thermal oxidation method. Spatially resolved cathodoluminescence (CL) intensity images were employed to correlate the luminescent properties with the investigated structure. Local CL monochromatic images revealed that the bodies of ZnO tower-like structures were the major source for a strong green emission. The depth-resolved UV and green CL emissions were examined by changing the accelerating voltage. A part of reabsorbed UV emission is converted into green emission and partly contributes the enhancement of green emission. [DOI: 10.1380/ejssnt.2009.358]

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The Ag-TeO₂-ZnTe MIS structures have been fabricated, and the current-voltage and the emission characteristics were investigated. The TeO₂, the natural oxide of the ZnTe substrates is used as the insulating layer, which is shown by the XPS measurement of the substrate surfaces before and after the diluted NH₄Cl etching. The MIS structure gives a clear rectifying behavior. Strong electroluminescence (EL) is observed under forward biases at room temperatures; the threshold voltage is about 16 V and the EL intensity increases up to 20 V. The EL spectrum starts from about 550 nm wavelength. The forward current increases and the EL intensity decreases as the temperature is increased. Plural current models explain both the bias and the temperature dependence of the EL intensities. [DOI: 10.1380/ejssnt.2009.362]

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The p-type Zn_0.8Mg_0.2O/n-type ZnO heterojunctions have been fabricated by a pulsed laser deposition (PLD) technique and the relations between the I-V and the electroluminescence (EL) characteristics were investigated. The ZnMgO film shows the best p-type characteristic for the 10% Sb concentration. The different Ga concentrations in n-type ZnO layers show different I-V and EL characteristics for the ZnMgO/ZnO heterojunctions. The 0.1% of Ga in the ZnO film shows the lowest resistivity (0.048 ohm·cm) and the highest electron mobility (59 cm²/Vs), however, the ZnMgO/ZnO junction shows only an Ohmic contact and no EL is observed. The heterostructure using the ZnO layer with 5.0% Ga shows the best rectifying behavior, however, no EL is observed. The 1.0% of Ga in the ZnO film shows the middle resistivity (0.51 ohm·cm) and the middle electron mobility (27 cm²/Vs) and the ZnMgO/ZnO heterojunction shows only a weak rectifying behavior but clear EL is observed. The threshold voltage of the EL is about 10V and the EL intensity is increased with the forward biases up to 20 V. These results indicate that the EL from ZnMgO/ZnO junctions does not necessarily require good ideality factors of the diodes. [DOI: 10.1380/ejssnt.2009.366]

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The luminescent properties of cerium doped yttrium silicate (Y₂SiO₅:Ce) nanocrystalline thin films that were grown during the systematic investigation of process parameters for pulsed laser deposition (PLD) (KrF laser, 248 nm on a silicon (Si)(100) substrate), were studied. Parameters such as ambient pressure (vacuum (5 × 10 ^-6 Torr), 1 × 10 ^-2 Torr and 1 Torr O₂ pressure), laser fluences (1.6 ± 0.1 J·cm^-2 and 3.0 ± 0.3 J·cm^-2) and substrate temperatures (400 and 600°C) were varied and the results are compared. The surface morphology was monitored by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and atomic force microscopy (AFM). The monoclinic X₁ crystal structures of the Y₂SiO₅:Ce films were studied with x-ray diffraction (XRD). The O₂ ambient pressure of 1 Torr resulted in the growth of a thin film consisting of spherically shaped nanoparticles and the thin film grown in vacuum resulted in a uniform thin film. The cathodoluminescence (CL) and photoluminescence (PL) intensity of the nanofilm is considerably higher than the uniform layer. The higher fluence resulted in a thicker thin film with a more compact agglomerated particle distribution. The lower fluence leads to a higher density distribution of smaller nanoparticles. The increase in substrate temperature to 600°C also resulted in a higher PL intensity. CL scanning images (with two different PMT voltages (650 and 850 eV)) were obtained on some of the thin films during SEM measurements. Emission from the thin films seems to occur from luminescent centres in the micron particles as well as from smaller particles around the bigger micron particles with the higher PMT voltage. [DOI: 10.1380/ejssnt.2009.369]

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Integration of non-crystalline and nanocrystalline thin films and nanocrystalline/non-crystalline composites in devices generally requires isotropic properties, and minimization of macroscopic strain. A novel pathway for obtaining isotropic properties and strain reductions is identified. The microscopic mechanism is based on nano-scale chemical bonding self organizations such as those that occur in intermediate phases, IPs, of non-crystalline glasses and thin films. This article emphasizes the importance on internal interfacial properties and the critical role they play. This understanding has emerged from studies on qualitatively different thin film materials, such as (i) As-Se thin film photoreceptors for electro-photographic applications, (ii) thin film transistor dielectrics for liquid crystal displays, (iii) high-k replacement dielectrics for SiO₂ in aggressively-scaled field effect transistors, and (iv) passive thin films for optically switched memory cells. [DOI: 10.1380/ejssnt.2009.375]

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This paper presents a spectroscopic study of interfacial bonding and substrate gate dielectric reactions for crystalline Ge-high-K gate dielectric hetero-structures. A novel processing sequence has been developed for i) depositing HfO₂ and Hf Si oxynitrides (HfSiON) onto N-passivated Ge(111) and (100) substrates in an attempt to prevent subcutaneous oxidation of the Ge substrate during dielectric deposition, and then ii) eliminating these Ge-N interfacial bonds during 650-800°C rapid thermal annealing in Ar. This approach has been motivated by previous spectroscopic studies which have demonstrated that the band-gaps of GeO₂ and Ge₃N₄ are reduced with respect to their Si counterparts, and cannot be used as interfacial layers (ILs) on n-type Ge substrates, or in n-metal oxide semiconductor field effect transistors (n-MOSFETs) in which a p-type Ge substrate has been inverted. Changes in interface bonding as a function of post-deposition annealing for Ge/HfO₂ and HfSiON, and HfO₂/HfSiON stacks have been studied by X-ray absorption and photoelectron spectroscopies, revealing i) intrinsic, or pre-existing conduction and valence band edge defects, and ii) process-induced changes in band edge defects as well. [DOI: 10.1380/ejssnt.2009.381]

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There are many examples of defects in strongly-correlated metal oxides for which density functional theory predicts electronic structures that qualitatively disagree with experimental data. This behaviour arises from the self-interaction error inherent to standard density functionals, and is demonstrated by both p- and n-type systems where the defect state is a small polaron associated with host lattice atoms. An approximate correction is to describe the electron—electron interactions in the orbitals of interest within the DFT+U formalism. This gives improved descriptions for systems where the states of interest are well represented by atomic-like orbitals. The qualitative failure of standard DFT and corresponding improvement achieved with DFT+U is illustrated for cases where the defect state is primarily associated with localised cation f and d states (O vacancies in CeO₂ and TiO₂) and anion p states (Li-doped MgO). [DOI: 10.1380/ejssnt.2009.389]

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Three competing defect configurations of Li-doping of MgO on the (100), (110) and (111) low index surfaces have been investigated using GGA + U. The three configurations investigated on each of the surfaces were: substitution of Li for Mg with the formation of a compensating oxygen hole state ([Li'_Mg—O^•_O]), substitution of Li for Mg with the addition of a Li surface interstitial ([Li'_MgLi^•_i]) and the clustering of two Li ions with the formation of a neutral [Li'_MgV^••_OLi'_Mg] oxygen vacancy. The electronic structure, geometry and energetics of these defects are examined, and the effect on catalytic activity is discussed. Hydrogen abstraction from methane on the three surfaces is also investigated. Our results demonstrate that the energetics associated with hydrogen adsorption are strongly surface dependent, with the (111) oxygen terminated surface indicated as being the most promising catalytically. [DOI: 10.1380/ejssnt.2009.395]

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Two new methods for fabrication of silicon-on-isolator (SOI) structures are studied. The first one is based on the formation of a template single crystalline Si-layer and combines encapsulated solid-vapor-phase epitaxy of silicon on rare-earth-metal-oxide layer, developed for fabrication of oxide/silicon/oxide heterostructures, subsequent chemical etching of the second oxide layer, followed by vapor-phase epitaxial growth of silicon on the template-silicon layer. In the second method, crystalline silicon islands serve as template for further growth of crystalline Si layer. Structural investigations show no interface and no noticeable differences in structure quality between these two silicon sub-layers grown on each other. Silicon-substrate/oxide/silicon heterostructure exhibits transition of the substrate crystalline structure with A/B/A twinning relationship. Initial stage of deposition of the template silicon is crucial for its structural quality. [DOI: 10.1380/ejssnt.2009.405]

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Complete optical characterization of SiO_x films non-uniform in thickness is performed using imaging spectroscopic reflectometry. It is shown that by using this technique it is possible to determine the area distribution of the local thickness (area map) of these films with arbitrary shape of this thickness non-uniformity. Furthermore, it is shown that the SiO_x films studied do not exhibit the area non-uniformity in dispersion (material) parameters and optical constants. This is possible because imaging spectroscopic reflectometry enables us to determine the area distributions of local thickness and local refractive index simultaneously in an independent way under the assumption that a suitable dispersion model of the refractive index of the films is used. In this paper the dispersion model corresponding to the Cauchy's formula is used. On the basis of this dispersion model the spectral dependence of the refractive index of the SiO_x films is determined. The method presented can be used to characterize the non-uniform films consisting of other non-absorbing materials. [DOI: 10.1380/ejssnt.2009.409]

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Interatomic potentials (IP) have demonstrated considerable application in the study of bulk and surfaces of ceria (CeO₂), and also the long range component in QM/MM calculations. Despite the development and ability of several IPs to reproduce the structural and dielectric properties of bulk ceria, in the absence of high quality electronic structure calculations it remains unclear how well these models perform when applied to surfaces. In this paper we present a comparison of several IPs from the literature in comparison with periodic density functional theory (GGA+U) for the calculation of the (111), (110) and (100) low index surfaces of ceria. While the IP approach reproduces the correct order of surface stability ((111)> (110) > (100)) and relaxation ((100)> (110) > (111)) found in the application of GGA+U, the surface energies calculated with IPs are considerably larger than those found with GGA+U. Based on the most comparable IP tested against GGA+U, we have performed trial QM/MM embedded-cluster calculations on the stoichiometric and defect (110) surface of ceria and compared the resulting defect energy with GGA+U. [DOI: 10.1380/ejssnt.2009.413]

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A reinvestigation of the alloying behavior between vapor deposited cerium and a Pt(111) substrate has led to a refined understanding of the structural and adsorption properties of Pt_xCe alloy surfaces. Systematic LEED experiments as a function of cerium coverage and annealing temperature enable a clearer correlation between a number of known as well as new surface alloy phases and transitions between them. Coverages of up to 1 ML Ce lead to the formation of a (2 × 2) LEED pattern. Initial coverages between 1 and 1.5 ML result in the formation of a (2 × 2)+(1.98 × 1.98)R30° structure. More than 2 ML Ce are needed to produce a pure (1.98 × 1.98)R30° structure and, finally, more than 3 ML Ce lead to the formation of a (1.98 × 1.98)+(1.98 × 1.98)R30° phase, after annealing to temperature of up to 1000 K. A comparison with the most relevant bulk Pt_xCe laves phases; i.e. Pt₅Ce, Pt₃Ce and Pt₂Ce, suggests a transition from a more “surface alloy like” character of the (2 × 2) structure to a more “bulk alloy like” character for the (1.98 × 1.98)-structure phases. CO adsorption experiments, using TPD and HREELS, suggest a pure Pt-kagomé surface termination of all the formed Pt_xCe alloy layers on Pt(111). [DOI: 10.1380/ejssnt.2009.421]

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GaSb(001) surface reconstructions with the experimentally observed (2×10) and c(2×10) symmetry are investigated employing density functional theory. Total energy calculations are carried out for a significant number of reconstructions, including the previously suggested metallic structures and new models which fulfill the electron counting rule. Special attention is given to the incorporation of Ga atoms during the initial steps of growth. It is shown, that none of these reconstructions is thermodynamically stable. This suggests that (2×10) and c(2×10) structures are kinetically stabilized under experimental conditions. [DOI: 10.1380/ejssnt.2009.429]

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The Ag adsorption induced √21×√21 superstructure on the Si(111)-5×2-Au structure at high temperature, namely √21×√21-(Au,Ag), has been studied using reflection high-energy positron diffraction. The profiles of the rocking curves and the intensity distributions in the diffraction pattern are similar to those from the Ag or Au adsorption induced √21×√21 superstructure (√21×√21-Ag and √21×√21-(Ag,Au)) on the Si(111)-√3×√3-Ag structure below room temperature. Assuming all of the adsorption atoms as the Ag atoms, we analyzed the atomic structure of the √21×√21-(Au,Ag) surface on the bases of the dynamical diffraction theory. We found that the structure model is almost the same as the √21×√21-Ag and √21×√21-(Ag,Au) surfaces. [DOI: 10.1380/ejssnt.2009.432]

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We determined the structures of Si(111)-4×1-In and Si(111)-8×2-In surfaces that are formed at 293 K and 60 K, respectively, through the rocking curve analyses of reflection high-energy positron diffraction (RHEPD). The structure of Si(111)-4×1-In surface is in good agreement with the zigzag chain structure determined by the surface X-ray diffraction [O. Bunk et al., Phys. Rev. B 59, 12228 (1999)]. In the Si(111)-8×2-In surface, In atoms are displaced in two dimensional directions from the positions of zigzag chain structure. The structure of Si(111)-8×2-In surface determined here is compatible to the hexagon structure predicted by the first principles study [C. González, F. Flores, and J. Ortega, Phys. Rev. Lett. 96, 136101 (2006)]. We determined the surface Debye-temperatures of 4×1 and 8×2 phases to be 80 K and 130 K, respectively. [DOI: 10.1380/ejssnt.2009.436]

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Despite the large lattice misfit and different lattice symmetry, it is possible to grow smooth and almost defect-free bismuth (Bi) films on a Si(001) substrate. High resolution low-energy electron diffraction measurements have confirmed that the (111) orientation is the preferred direction of the growth. However, at low temperature and low coverage regime, rotationally disordered crystallites of (110) orientation are also observed. After the formation of a continuous layer at 5.6 bilayer (2.2nm), the growth occurs in a bilayer-by-bilayer fashion at 150 K. The remaining lattice mismatch of 2.3% is accommodated by a periodic array of interfacial misfit dislocations, which gives rise to a periodic surface height undulation with sub-ångström amplitude. Additional growth to the desired thickness caps the height undulation resulting in an atomically smooth surface (terrace size > 100nm). The Bi(111) film is relaxed to bulk lattice constant and shows excellent crystalline quality with an abrupt interface to the Si substrate. [DOI: 10.1380/ejssnt.2009.441]

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The growth as well as the compositional, electronic and structural properties of thin Au films deposited on a Pd(110) single crystal have been studied by means of ultraviolet photoelectron spectroscopy (UPS), photoemission of adsorbed xenon (PAX) and scanning tunneling microscopy (STM) as a function of film thickness (ranging from submonolayer amounts up to multilayers) and temperature. Our investigations indicate a Volmer-Weber growth mode of Au on Pd(110) at a deposition temperature of 300 K and below. As former studies already have shown, depositing Au amounts of less than 1 ML results in the formation of unreconstructed pseudomorphic Au islands. Above a critical thickness of 2 ML the formation of a (1 × 2) missing-row reconstruction typical for Au can be observed. This reconstructed Au bilayer is still in registry with Pd(110) and, thus, strained. Furthermore, our experiments show a strong temperature dependence of the surface morphology. Au multilayers prepared at 150 K, which are already quite flat, undergo a weak smoothening of the topmost atomic layer by annealing the sample up to 350 K. At a surface temperature of ∼ 450 K the diffusion of Au atoms into the bulk is initiated at the Au-Pd interface. Annealing a 3 ML thick Au film to 600 K finally results in the formation of an Au-Pd surface alloy, which is stable up to 900 K. A complete loss of Au from the surface can be detected at around 1050 K. Adsorption of CO as a probe molecule on the Au containing surfaces is only possible at low temperatures. [DOI: 10.1380/ejssnt.2009.448]

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We suggest a link between film morphology and electrical properties of a crystalline organic semiconductor: polymer insulating blend. TIPS-Pentacene (6,13-bis(triisopropylsilylethynyl) pentacene) [J. Am. Chem. Soc. 123, 9482 (2001)] is formulated with various amorphous and semi-crystalline side chain aromatic low permittivity dielectric polymers. Film structure investigated by AFM microscopy and XPS gives invaluable information regarding film morphology and confirms potential intermolecular interaction. All these morphological observations were linked to the electrical characterisation of organic thin film transistors (OTFTs) and the determination of saturated hole mobility value. When an amorphous binder is used the more dilute the TIPS-pentacene the lower the saturated hole mobility value. When a semi-crystalline binder is used it is possible to massively dilute TIPS-pentacene within the polymer dielectric without loosing either the crystalline structure of the material or the electronic properties. Besides phase segregation, enrichment of the active interface in TIPS-Pentacene is demonstrated. [DOI: 10.1380/ejssnt.2009.455]

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This work examines diamond-like carbon (DLC) coatings deposited by plasma enhanced chemical vapour deposition (PECVD) as an environmentally friendly alternative to chromium plating in restoration of worn or damaged aircraft components. DLC coatings offer superior mechanical properties; however, high internal stresses and poor adhesion can prevent the deposition of thick films. This work examines a series of layered structures based on epoxy-resin interlayers with DLC applied as a surface film. Wear testing and examination with scanning electron microscopy and atomic force microscopy lead to the development of an optimum DLC/epoxy system with wear characteristics superior to those of chromium-plated steel. This new coating system has a great potential in restoring aircraft components in a more efficient and environmentally friendly manner. [DOI: 10.1380/ejssnt.2009.459]

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WO₃ thin films were deposited by RF magnetron sputtering at different deposition angles and modifications in their morphological properties investigated, aiming applications as the cathode electrodes in lithium microbatteries. The surface properties of the produced samples such as roughness exponent, surface area, and grain size were analyzed by atomic force microscopy. The roughness exponents values that characterize the events through the morphology changes during the growth of the films were in the range of α = 0.67-0.77, for deposition angles between 0° and 82°. Two different diffusion events were observed in the deposition processes, a less atomic species diffusion at angles between 30° - 50° and high diffusion at both extremes of deposition angles of 0° or 82°. The samples obtained at less diffusion deposition processes exhibited a higher roughness. The electrochemical behavior of the studied WO₃ thin films revealed a strong dependence of their charge capacity on the deposition conditions with a clear correlation between the morphological properties of the films (grain size and roughness) and electrochemical performance. [DOI: 10.1380/ejssnt.2009.465]

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Microphase separation is readily achieved in both PS-b-PEO diblock copolymer thin films and in PS homopolymer/PS-b-PEO polymer blends via solvent annealing. In situ synthesis of PS homopolymer with a symmetric PS-b-PEO diblock copolymer results in a cylindrical structure rather than a predicted lamellar morphology for the diblock due to the increased amount of PS present. Solvent annealing in toluene results in ordered structures of PEO cylinders orientated parallel to the substrate in the PS matrix. Solvent annealing in a mixed toluene/water environment creates an essentially `neutral' solvent environment resulting in a perpendicular orientation. PS-b-PEO/PS thin films with cylinders orientated parallel have a smaller cylinder centre-to-cylinder centre spacing than films with cylinders orientated perpendicular due to the location to the PS homopolymer. If the molecular weight of the diblock is sufficiently low for a given Flory-Huggins parameter microphase separation will not occur. On topographically defined substrates the solvent annealing process does not provide sufficient mobility to the polymer to allow mass transport of polymer from the crests into the channels and only limited alignment is achieved. [DOI: 10.1380/ejssnt.2008.471]

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We report on a scanning tunneling microscopy (STM) study of Mg-O surfaces obtained from ultra-thin Mg/Ag(111) layers exposed to different doses of oxygen at room temperature. Large scale images of any of the Mg-O surfaces show faintly corrugated alignments of 2-2.5 nm wide elementary dots. For adequate O₂ pressure with respect to the nominal Mg coverage, the dots are aligned along the < 112 > directions of silver. A hexagonal array of dots with a 4.5 nm periodicity may even be obtained, which we attribute to an epitaxial Mg-O (111) layer with in-plane spacing equal to 3.0 or 3.2 nm. [DOI: 10.1380/ejssnt.2009.476]

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In this paper the ternary segregation behaviour of Bi and S in a dilute Cu(Bi,S) polycrystalline crystal was investigated by using Auger electron spectroscopy to monitor the surface concentrations of Bi and S during constant temperature segregation measurements that were preformed in the temperature range 723 to 973 K at 50 K intervals. It was found that initially both Bi and S segregated to the surface. At first the segregation rate of S was higher than that of Bi. The Bi segregated to the surface until it reached a surface maximum concentration (2-6%) and subsequently the segregation rate of both S and Bi decreased and the Bi started to desegregate. The S replaced the Bi completely on the surface. Diffusion parameters, namely the activation energy (Q) and pre-exponential factor (D₀) were determined for Bi as 181.6 kJ·mol^-1 and 3.7 × 10^-5 m²·s^-1, respectively. The S concentration in the crystal was unknown and the S segregation profiles were used to estimate the S concentration in the Cu crystal as 122 ± 12 ppm. [DOI: 10.1380/ejssnt.2009.480]

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Ultra-thin films of ⁵⁷Fe deposited on silicon substrates and SiO_xC_yH_z support layers and subsequently oxidized in laboratory atmosphere are studied by two optical methods: the combination of UV/VIS/NIR spectroscopic ellipsometry and spectrophotometry, used to find layer thicknesses and optical constants, and X-ray specular reflectometry, used to obtain the electron density depth profile. The results of both methods are compared and found to be in a relatively good agreement. [DOI: 10.1380/ejssnt.2009.486]

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Based on modification of beta-sheeted protein structures in biosynthesis stage selfassemblage of 3D structures on solid state surfaces is investigated. A set of hybrid proteins containing the abeta40 peptide domain are constructed and characterized. The extended biomolecular structures are immobilised on the solid surfaces. Self assembled hybrid structures on the surface are obtained by deposition of the biomolecular conglomerates from buffer solutions. The surfaces of mica, SiO₂, SnO and In₂O₃ are covered with the biomolecular layer. Formation of hybrid structures containing beta-sheeted fibrils is dependent on immobilisation period and origin of the solid surface. Morphology, mechanical and electrical properties are described by scanning probe microscope. Stabile fibrils of diameter about 2 nm and length of about 100-1000 nm are detected for lysozyme while Abeta40 peptide base proteins and TrxAbeta40 mutants result in specific structures. The biomolecular layers were described by analytical model based on digital representation of the surface profile data and analysis of the power spectral density function. [DOI: 10.1380/ejssnt.2009.491]

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Thin films of AlN, CrN and Al_1-xCr_xN were grown epitaxially on c-cut sapphire by radio frequency (RF) plasma assisted pulsed laser deposition (PLD). The PLD growth mode employed for these Al_1-xCr_xN films was by delta doping layers of CrN 0.05-0.10 nm thick between layers of AlN of approximately 3.6 nm thick giving an estimated 1.3% and 2.5% Cr doping. The substrate temperature, nitrogen pressure and power parameters of the RF plasma were varied to optimize crystalline growth. X-ray diffraction (XRD) confirmed hexagonal wurtzite thin film growth of highly crystalline AlN and highly crystalline cubic CrN. The electronic structure of these thin films was examined by x-ray absorption (XAS) and soft x-ray emission spectroscopy (XES) at the N K edge. These measurements are compared with the results of density functional calculations for wurtzite-AlN, cubic-CrN and wurtzite-Al_1-xCr_xN. [DOI: 10.1380/ejssnt.2009.497]

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A simple method for the fabrication of films with an high density of nanometric metal grains is presented and discussed. The method is based on the successive evaporation of different metals (Au, Al and In), with different melting points: after each evaporation, rapid thermal annealing treatments are used to induce agglomeration of the deposited material. The nanograin agglomeration (in particular of the Al film) resulted strongly dependent on the previous nanograin (gold) distribution and concentration. Statistics of gold based nanograin films, deposited on silicon dioxide, are presented for different gold thickness and annealing parameters. Results on Al induced agglomeration of a successively evaporated thin film are shown for different Au nanoparticle distribution and concentration. A final indium deposition, with suitable annealing temperature and time, produces films with a very high density of metal nanoparticles (more than 2000 nanograins/μm², average radius between 5 and 10 nm). [DOI: 10.1380/ejssnt.2008.503]

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It is well known that the Taiwan Semiconductor industries play the very key roles for the worldwide IC foundry, and the advanced research of nanoelectronics is the lifeline for its long term developments. Professor Huey-liang Hwang effectively integrated the most outstanding research team and resource in Taiwan on the National Project on Nanometer CMOS Transistors for the 21 century, which is sponsored by the Ministry of Economic Affairs of ROC. A dozen of Professors from NTHU (National Tsing Hua University) with expertise at the novel materials and analysis and NCTU (National Chiao Tung University) with expertise at devices and reliability are devoted to the studies and are in collaboration with the world-wide-known company such as TSMC, and breakthrough of the key technologies of 45-32 nm technologies are achieved. The objective of this project is focused on the development of advanced metal gate/high-k MOSFET for 45 nm node generation and beyond, the efforts include the thermal stability of HfO₂, HfAlO_x alloy and Al₂O₃/HfO₂ stack, prepared by ALD were compared, the incorporation of Al in alloy form gave superior characteristics by retaining an amorphous structure up to 1000°C, which suppress the leakage current and retards growth of the interfacial layer giving the least increment of EOT and interface traps. Besides, by incorporating Al into TiO₂ gave an EOT value of the Al₂O₃/TiAlO_x/Al₂O₃ film down to 0.8 nm. Furthermore, high selectivity was obtained via etching the HfAlO and silicon wafer with pattern using the ICP Plasma. In this project, YbSi metal gate for n-MOSFET and IrSi metal gate p-MOSFET were successfully fabricated for the HfAlON MESFET. The results showed the good effective workfunction of 4.15 and 4.9 eV and no degradation of gate dielectric current and mobility in the Yb_xSi/HfAlON and Ir_xSi/HfAlON FUSI-gates by reducing the metal diffusion at lower temperatures. [DOI: 10.1380/ejssnt.2009.507]

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The evaluation of protein structural change is crucial for the study of protein-protein interactions and protein conformational changes. Time-of-flight secondary ion mass spectrometry (TOF-SIMS) was used to detect pH dependent structural change in staphylococcal protein A (SpA), which is well known to the bind Fc region of immunoglobulins. TOF-SIMS spectra of SpA-immobilized samples in a pH 7 solution, in an acidic solution, and in a pH 7 solution after having been soaked in an acidic solution, respectively, were compared to select fragment ions specific to normal SpA at pH 7 using spectral analysis techniques such as principal component analysis (PCA) and the mutual information method. A fragment ion depending on change in the B and E domains of SpA were detected with this method. These findings demonstrate that structural change of SpA depending on pH change can be evaluated with TOF-SIMS together with spectrum analysis methods for the multivariate data. [DOI: 10.1380/ejssnt.2009.715]

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The last sentence of the abstract in Ref.[M. Mantilla, N. Jedrecy, R. Lazzari, and J. Jupille, e-J. Surf. Sci. Nanotech. 7, 476 (2009).] should be corrected as follows: “A hexagonal array of dots with a 4.5 nm periodicity may even be obtained, which we attribute to an epitaxial Mg-O (111) layer with in-plane spacing equal to either 0.3 or 0.32 nm.” [DOI: 10.1380/ejssnt.2009.529]

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In this article [Y. Miyamoto, et al., e-J. Surf. Sci. Nanotech. 7, 107 (2009)], we discussed formation of graphene on Si substrates assuming that the pre-grown 3C-SiC films on the Si(110) substrate are (111)-oriented. Later investigations suggest, however, that the 3C-SiC films used in this study are dominated by (110)- oriented portion, with the (111)-orientation being the minority. The comments on the (111)-orientation of the 3C-SiC films should therefore be omitted. This revision, however, does not affect our observation of graphene formation on Si substrates and the analyses thereon.[DOI: 10.1380/ejssnt.2009.699]

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In this article [M. Suemitsu, et al., e-J. Surf. Sci. Nanotech. 7, 311 (2009)], we discussed formation of graphene on Si substrates assuming that the pre-grown 3C-SiC films on the Si(110) substrate are (111)-oriented. Later investigations suggest, however, that the 3C-SiC films used in this study are dominated by (110)-oriented portion, with the (111)-orientation being the minority. The comments on the (111)-orientation of the 3C-SiC films should therefore be omitted. This revision, however, does not affect our observation of graphene formation on Si substrates and the analyses thereon. [DOI: 10.1380/ejssnt.2009.700]

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In this article [1], one of the coauthors, B. Krenzer, is missing in the author list by mistake. The correct author list is the same as the one shown in this erratum.

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In the article, Eqs. (8) and (9) should be corrected. In addition, the second legend in Fig. 5 should be corrected. [DOI: 10.1380/ejssnt.2009.836]

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