This paper characterizes transparent current mirrors with n-type amorphous gallium-indium-zinc-oxide (a-GIZO) thin-film transistors (TFTs). Two-TFT current mirrors with different mirroring ratios and a cascode topology are considered. A neural model is developed based on the measured data of the TFTs and is implemented in Verilog-A; then it is used to simulate the circuits with Cadence Virtuoso Spectre simulator. The simulation outcomes are validated with the fabricated circuit response. These results show that the neural network can model TFT accurately, as well as the current mirroring ability of the TFTs. © 2005-2012 IEEE.

The present work focuses on a qualitative analysis of localised I-V characteristics based on the nanostructure morphology of highly dense arrays of p-type NiO nano-pillars (NiO-NPs). Vertically aligned NiO-NPs have been grown on different substrates by using a glancing angle deposition (GLAD) technique. The preferred orientation of as grown NiO-NPs was controlled by the deposition pressure. The NiO-NPs displayed a polar surface with a microscopic dipole moment along the (111) plane (Tasker's type III). Consequently, the crystal plane dependent surface electron accumulation layer and the lattice disorder at the grain boundary interface showed a non-uniform current distribution throughout the sample surface, demonstrated by a conducting AFM technique (c-AFM). The variation in I-V for different points in a single current distribution grain (CD-grain) has been attributed to the variation of Schottky barrier height (SBH) at the metal-semiconductor (M-S) interface. Furthermore, we observed that the strain produced during the NiO-NPs growth can modulate the SBH. Inbound strain acts as an external field to influence the local electric field at the M-S interface causing a variation in SBH with the NPs orientation. This paper shows that vertical arrays of NiO-NPs are potential candidates for nanoscale devices because they have a great impact on the local current transport mechanism due to its nanostructure morphology.

We present the results obtained with an extended-gate ISFET totally based on amorphous oxides (GIZO as the semiconductor, {\textless}formula formulatype="inline"{\textgreater}{\textless}tex Notation="TeX"{\textgreater}{\$}{\{}hbox{\{}Ta{\}}{\}}{\_}{\{}2{\}}{\{}hbox{\{}O{\}}{\}}{\_}{\{}5{\}}{\{}hbox{\{}:SiO{\}}{\}}{\_}{\{}2{\}}{\$}{\textless}/tex{\textgreater} {\textless}/formula{\textgreater} as the dielectric and {\textless}formula formulatype="inline"{\textgreater}{\textless}tex Notation="TeX"{\textgreater}{\$}{\{}hbox{\{}Ta{\}}{\}}{\_}{\{}2{\}}{\{}hbox{\{}O{\}}{\}}{\_}{\{}5{\}}{\$}{\textless}/tex{\textgreater} {\textless}/formula{\textgreater} as the sensitive layer). A full characterization of the device was performed with constant ionic strength pH buffer solutions, revealing a sensitivity of 40 mV/pH with small hysteresis, and good linearity in the pH 4{&}{\#}x2013;pH 10 range buffer solutions. These results clearly show that it is possible to produce room-temperature disposable and low cost bio-sensors.

The magnetic and electrical properties of Ni implanted single crystalline TiO2 rutile were studied for nominal implanted fluences between 0.5?1017 cm−2 and 2.0?1017 cm−2 with 150 keV energy, corre- sponding to maximum atomic concentrations between 9 at{%} and 27 at{%} at 65 nm depth, in order to study the formation of metallic oriented aggregates. The results indicate that the as implanted crystals exhibit superparamagnetic behavior for the two higher fluences, which is attributed to the formation of nanosized nickel clusters with an average size related with the implanted concentration, while only paramagnetic behavior is observed for the lowest fluence. Annealing at 1073 K induces the aggregation of the implanted nickel and enhances the magnetization in all samples. The associated anisotropic behavior indicates preferred orientations of the nickel aggregates in the rutile lattice consistent with Rutherford backscattering spectrometry—channelling results. Electrical conductivity displays anisotropic behavior but no magnetoresistive effects were detected.

A nano-sized Magnesia–Zirconia (nano-MgO–ZrO2) catalyst was prepared by a simple ultradilution co-precipitation method and by using inexpensive precursors. The nano-MgO–ZrO2 was extensively characterized by SIMS together with other analytical techniques such as X-ray diffraction (XRD) and transmission electron microscopy (TEM). The nano-MgO–ZrO2 catalyst proved to be very efficient for the reduction of carbonyl compounds and multicomponent reactions under mild reaction conditions. The recyclability and reusability of the nano-MgO–ZrO2 catalyst has been tested.

Thin-films of copper oxide Cu O were produced by thermal oxidation of metallic copper (Cu) at different tempera- tures (150–450 C). The films produced at temperatures of 200, 250 and 300 C showed high Hall motilities of 2.2, 1.9 and 1.6 cm V s , respectively. Single Cu O phases were obtained at 200 Cand its conversion toCuO starts at 250 C. For lower thick- nesses 40 nm, the films oxidized at 250 Cshowed a complete conversion to CuO phase. Successful thin-film transistors (TFTs) were produce by thermal oxidation of a 20 nm Cu film, obtaining p-type Cu O (at 200 C) and CuO (at 250 C) with On/Off ratios of 6 10 and 1 10 , respectively.

The effect of post-deposition annealing temperature on the pH sensitivity of room temperature RF sputtered Ta O was investigated. Structural and morphological features of these films were analyzed before and after annealing at various tem- peratures. The deposited films are amorphous up to 600 Cand crystallize at 700 C in an orthorhombic phase. Electrolyte-insu- lator-semiconductor (EIS) field effect based sensors with an amor- phousTa O sensing layer showed pHsensitivity above 50 mV/pH. For sensors annealed above 200 C pH sensitivity decreased with increasing temperature. Stabilized sensor response andmaximum pHsensitivitywas achieved after low temperature annealing at 200 C, which is compatible with the use of polymeric substrates and application as sensitive layer in oxides TFT-based sensors

The effect of post-deposition annealing temperature on the pH sensitivity of room temperature RF sputtered Ta2O5 was investigated. Structural and morphological features of these films were analyzed before and after annealing at various temperatures. The deposited films are amorphous up to 600 °C and crystallize at 700 °C in an orthorhombic phase. Electrolyte-insulator-semiconductor (EIS) field effect based sensors with an amorphous Ta2O5 sensing layer showed pH sensitivity above 50 mV/pH. For sensors annealed above 200 °C pH sensitivity decreased with increasing temperature. Stabilized sensor response and maximum pH sensitivity was achieved after low temperature annealing at 200 °C, which is compatible with the use of polymeric substrates and application as sensitive layer in oxides TFT-based sensors.

In this work Laponite was combined with a modified abundant natural polymer, (caboxymethyl cellulose), acrylic sodium salt polymer and lithium perchlorate aiming to produce inexpensive and sustainable nanocomposite electrolytes for functional electrochemical devices. Optical, electrochemical, structural, morphological and rheological characterization was performed in order to evaluate their properties and potential advantages as electrolyte. It was verified that the addition of Laponite led to an ionic conductivity at room temperature (25 C) in the range of 6 to 9 ?? 10- 5 Scm - 1 this value being then determined by the composition of the nanocomposite. These electrolytes were applied to electrochromic devices using evaporated nickel oxide thin film as the electrochromic layer. The devices exhibited a significant transmittance modulation that exceeds 45 {%} at 600 nm. ?? 2013 Elsevier B.V.

Abstract.  The concept of intermediate band solar cell (IBSC) is, apparently, simple to grasp. However, since the idea was proposed, our understanding has improved and some concepts can now be explained more clearly than when the concept was initially introduced. Clarifying these concepts is important, even if they are well known for the advanced researcher, so that research efforts can be driven in the right direction from the start. The six pieces of this work are: Does a miniband need to be formed when the IBSC is implemented with quantum dots? What are the problems for each of the main practical approaches that exist today? What are the simplest experimental techniques to demonstrate whether an IBSC is working as such or not? What is the issue with the absorption coefficient overlap and the Mott's transition? What would the best system be, if any?

{Three new emissive 8-aminoquinoline derived probes (1)-(3) and one dinuclear Zn(II) complex (4) were synthesized and fully characterized. Their absorption spectra show maxima at 310-336 nm, and fluorescence emission between 456 and 498 nm. Compound (1) was characterized by single crystal X-ray diffraction. The effect upon Zn(II) and Cu(II) coordination to compounds (1)-(3) was studied by monitoring the changes in absorption and fluorescence spectra, and complemented by calculation of metal-ligand stability constants. The results indicate that compound (3) is the one that presents the most favorable geometry for coordinating two metal cations, fact that is confirmed by the synthesis of the dinuclear complex (4), with similar molecular geometry. (C) 2011 Elsevier B.V. All rights reserved.}