Lyotropic 'hairy' TiO2 nanorods.

We experimentally demonstrated the great advantages of a high dielectric constant thin film electromagnetic bandgap (EBG) power distribution network (PDN) for the suppression of power/ground noises and radiated emissions in high-performance multilayer digital printed circuit boards (PCBs). Five-layer test PCBs were fabricated and their scattering parameters measured. The power plane noise and radiated emissions were measured, investigated and related to the PDN impedance. This successfully demonstrated that the bandgap of the EBG was extended more than three times, covering a range of hundreds of MHz using a 1-cm /spl times/ 1-cm EBG cell, the SSN was reduced from 170 mV to 10 mV and the radiated emission was suppressed by 22 dB because of the high dielectric constant thin film EBG power/ground network.

The development of high-dielectric constant film materials is essential for future active and passive nanoelectronics devices. By integrating combinatorial synthesis, high throughput material development, and interface analysis, we have developed a high-dielectric constant Bi-based relaxor ferroelectric film material, x[BaTiO3]–(1−x)[Bi(Mg2/3Nb1/3)O3] (BT–BMN), for film capacitors. To increase the dielectric constant, and its thermal stability, of the above relaxor ferroelectric films, a periodic Ta doping structure was introduced by combinatorial method. The periodic insertion of BT–BMN layers with a high Ta concentration eliminated the dielectric constant decrease and also the Bi segregation encountered in BT–BMN films under high-temperature conditions. Upon optimizing the BT/BMN ratio in the stack structure, the BT–BMN films exhibited a high dielectric constant (>500) and an excellent thermal stability, less than 8% in the temperature range from room temperature to 400 °C

Utilizing high dielectric constant thin film for integrated capacitors is one important factor in downsizing microelectronic devices and systems. SrTiO3 is a candidate material since it has a high dielectric constant and a relatively low dielectric loss. In the present work SrTiO3 thin films have been grown from a Sr-enriched ceramic target (Sr1.1Ti0.9O3) on Cu-coated glass fiber laminate substrates at ambient temperature using rf magnetron sputtering. The obtained films has low crystallinity. Film composition was determined to be Sr0.62Ti 1.0O3.0. The dielectric properties were characterized on a 1 fun thick film in the frequency range between 1 kHz and 1 MHz. The dielectric constants of the films were found to spread between 40–70 and the dissipation factors decreased with frequency down to 8×10−4 at 1 MHz.

The dielectric properties of high dielectric constant thin films on the electrode sidewalls were evaluated for the first time, and sputter-deposited (Ba,Sr)TiO/sub 3/ thin films were characterized on the sidewalls of RuO/sub 2/ electrodes patterned down to submicron sizes. A fairly large step coverage around 50% was obtained for (Ba,Sr)TiO/sub 3/. The /spl epsiv//sub r/ value for (Ba,Sr)TiO/sub 3/ films on the sidewalls was the same as that for the films on the top surface, but the leakage current was larger. The (Ba,Sr)TiO/sub 3/ films on the sidewalls were found to be well crystallized, however, the grain size was smaller, and a porous structure was observed by TEM analysis.

High dielectric constant titanium dioxide thin films have been formed on silicon substrates by the rapid thermal oxidation of evaporated titanium. Oxidation of titanium at temperatures between 450 and 800 °C for periods of 1–60 s has been studied. Rutile polycrystalline layers of 800–2000 Å thickness were formed. Dielectric constants were in the range of 58–77 for titanium dioxide on silicon. High oxidization temperatures gave leakage currents of 10−7 A at 0.3 MV cm−1 for a 1500-Å-thick layer, and potential is seen for improved results with thinner layers.

The fabrication of high dielectric constant lead zirconate titanate thin films for dynamic random access memory application involves post-deposition annealing to convert the low dielectric constant pyrochlore phase to the desired high dielectric constant perovskite phase. The results of our experiments detailing the dielectric characteristics such as degradation field (the electric field at which a sudden increase in leakage takes place), leakage current density, time-dependent dielectric breakdown characteristics, charge storage density, coercive field, and charge storage density are reported. The charge storage density was measured using both double-bipolar pulses and quasistatic capacitance-voltage techniques. The results of these two measurement techniques are discussed for oxygen and nitrogen annealed films. Additionally, a comparative study of the phase transformation kinetics when the post-deposition annealing is carried out in a nonoxidizing ambient such as nitrogen, as against an oxidizing ambient (pure oxygen), is detailed.

High-repetition rate diode-pumped sub-ps lasers are widely used in the industrial sector for high-quality material processing applications. However, for their reliable operation, it is crucial to study the power handling capabilities of the optical components used in these systems. The optical components, such as mirrors, gratings, dichroic filters, and gain media, are designed based on dielectric thin films. When subjected to high-intensity laser radiation, the phenomenon of laser-induced contamination (LIC) can lead to the growth of a nanometric, highly absorbent layer on an irradiated optical surface, which can result in transmission or reflection loss and eventual permanent damage. In this study, we investigate LIC growth on dielectric oxide thin films in an air environment irradiated by MHz sub-ps laser at 515 nm. We examine the effect of thin film deposition method, material, and thickness on LIC growth dynamics. The irradiated spots on the surface are inspected using multiple observation methods, including white light interference microscopy and fluorescence imaging. Our results show that the LIC growth dynamics depend on the laser intensity and irradiation time and can be affected by the thin film deposition method, material, and thickness. These findings could be used to inform the development of more resistant optical components, ensuring long-term reliable laser operation required for industrial applications. The study highlights the need for validating optical components using tests that closely mimic real-world applications and provides insight into the complex processes that lead to LIC.

Ag-Ag2S quantum-dots modified TiO2 nanorod arrays with enhanced photoelectrochemical and photocatalytic properties

Ultrathin alumina wrapped TiO2 nanorods for enhance photoelectrochemical performance via atomic layer deposition method

The paper reports a method of depositing SiO2, SiNx, a:Si, Si3N4 and SiOxNy dielectric thin films by electron cyclotron resonance plasma chemical vapor deposition (ECR CVD) on InP, InGaAs and other compound semiconductor optoelectronic devices,and give a technology of depositing dielectric thin films and optical coatings by ECR CVD on Laser's Bars. The experiment results show the dielectric thin films and optical coatings are stable at thermomechanical property,optical properties and the other properties. In addition, the dielectric thin film deposition that there is low leakage current is reported for using as diffusion and ion implatation masks in the paper. In the finally, the dielectric film refractive index can be accurately controlled by the N-2/O-2/Ar gas flow rate.

We report herein the growth Titanium Dioxide (TiO2) nanorods on FTO substrate with different aspect ratio. It is observed that the photo anodic behaviour is highly influenced by the aspect ratio of as -grown TiO2 nanorods. Hydrolysis of TiCl4 leads to the formation of TiO2 nanorods on FTO substrate. Nanorods of different aspect ratio are obtained by varying the concentration (0.1M, 0.2M) of TiCl4. The XRD pattern confirms the formation of rutile, tetragonal TiO2 nanorods with high crystallinity. From the FESEM images, the length and width of the nanorods are observed. The aspect ratio is found to be 151 for low concentration TiO2 nanorod array (TR1) and 330 for high concentration TiO2 nanorod array (TR2). The specific surface area, porosity of the samples was calculated using Brunauer–Emmett–Teller (BET) analysis. Superior surface properties are noticed in the case of TiO2 nanorods with high aspect ratio. The photovoltaic activity of TiO2 nanorods with high aspect ratio is found to be relatively high as compared to those with low aspect ratio.

Thermal radiative emission from a hot surface to a cold surface plays an important role in many applications, including energy conversion, thermal management, lithography, data storage and thermal microscopy. Recent studies on bulk materials have confirmed long-standing theoretical predictions indicating that when the gap between the surfaces is reduced to tens of nanometres, well below the peak wavelength of the blackbody emission spectrum, the radiative heat flux increases by orders of magnitude. However, despite recent attempts, whether such enhancements can be obtained in nanoscale dielectric films thinner than the penetration depth of thermal radiation, as suggested by theory, remains experimentally unknown. Here, using an experimental platform that comprises a heat-flow calorimeter with a resolution of about 100 pW (ref. 7), we experimentally demonstrate a dramatic increase in near-field radiative heat transfer, comparable to that obtained between bulk materials, even for very thin dielectric films (50-100 nm) when the spatial separation between the hot and cold surfaces is comparable to the film thickness. We explain these results by analysing the spectral characteristics and mode shapes of surface phonon polaritons, which dominate near-field radiative heat transport in polar dielectric thin films.

We consider the slow highly charged ions impinging upon a metal surface covered with a thin dielectric film, and formation of the surface nanostructures (craters) from the standpoint of the required energy. For the moderate ionic velocities, the size of the surface features depends on the deposited kinetic energy of the projectile and the ionic neutralization energy. The neutralization energy is calculated by employing the recently developed quasi-resonant two-state vector model for the intermediate Rydberg state population and the micro-staircase model for the cascade neutralization. The electron interactions with the ionic core, polarized dielectric and charge induced on the metal surface are modelled by the appropriate asymptotic expressions and the method for calculation of the effective ionic charges in the dielectric is proposed.The results are presented for the interaction of ions (velocity a.u.; ) with the metal surface (Co) covered with a thin dielectric film, for model values of dielectric constant inside the interaction region. In the absence of dielectric film, the neutralization energy is lower than the potential (ionization) energy due to the incomplete neutralization. The presence of dielectric film additionally decreases the neutralization energy. We calculate the projectile neutralization energy in the perturbed dielectric (perturbation is caused by the ionic motion and the surface structure formation). We correlate the neutralization energy added to the deposited kinetic energy with the experimentally obtained energy necessary for the formation of the nano-crater of a given depth.

In recent years, titanium dioxide (TiO2) has emerged as one of the most exceptional nanomaterials, attracting interest from experts throughout the globe. In addition to having a band gap of 3.2 eV, TiO2 has outstanding optical, structural, electrical, and photocatalytic capabilities that may be used in the semiconductor industry. However, because of its weak conductivity and capacitance, TiO2 has not been able to reach its full potential. In order to realise its full potential, researchers have devised a variety of methods, including hydrothermal deposition, sol-gel-assisted template deposition, chemical vapor deposition, electrochemical anodisation, hydrothermal deposition, and metal oxide doping. Doping TiO2 with metal oxides has been shown to significantly enhance its properties, which may improve its qualities. The primary goal of this study is to provide an overview of various research studies on the influence of the metal oxide dopant on the final properties of titanium dioxide (TiO2) nanorod arrays.

Surface sensitization of TiO2 nanorod mats by electrodeposition of ZIF-67 for water photo-oxidation