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We report the structural characterization and nanomechanical properties of platinum (Pt) thin films prepared through facile electrochemical synthesis. The Pt thin films were coated onto indium tin oxide (ITO)/glass substrates by two-electrode electrochemical deposition at room temperature. They were characterized using X-ray diffraction, scanning electron microscopy, and atomic force microscopy for structural and morphological analyses. Indentation depth-dependent hardness and elastic modulus of the prepared films were analyzed using the nanoindentation technique. Furthermore, the mechanical properties of the ITO/glass substrates were also investigated to understand the influence of the substrate on the film properties. The prepared films showed reasonable mechanical and structural properties suitable for device applications. Finally, the photoconductivity effect of the prepared Pt film was also studied to determine its suitability for device applications. The Pt film was also coated on Cu plates to check substrates effects on this electrochemical deposition, and found that the Cu plates produced well adherent smooth films.

Organic thin film transistors were fabricated using evaporated zinc phthalocyanine as the active layer. Parylene film prepared by chemical vapour deposition was used as the organic gate insulator. The annealing of the samples was performed at 120 °C for 3 h. At room temperature, these transistors exhibit p-type conductivity with field-effect mobilities ranging from 0·025–0·037 cm2/Vs and a (Ion/Ioff) ratio of ∼103. The effect of annealing on transistor characteristics is discussed.

We report an efficient method for growing NiO nanostructures by oblique angle deposition (OAD) technique in an e-beam evaporator for supercapacitor applications. This facile physical vapor deposition technique combined with OAD presents a unique, direct, and economical route for obtaining high width-to-height ratio nanorods for supercapacitor electrodes. The NiO nanostructure essentially consists of nanorods with varying dimensions. The sample deposited at OAD 75° showed highest supercapacitance value of 344 F/g. NiO nanorod electrodes exhibits excellent electrochemical stability with no degradation in capacitance after 5000 charge–discharge cycles. The nanostructured film adhered well to the substrate and had 131% capacity retention. Peak energy density and power density of the NiO nanorods were 8.78 Wh/kg and 2.5 kW/kg, respectively. This technique has potential to be expanded for growing nanostructured films of other interesting metal/metal oxide candidates for supercapacitor applications.

Synthesis of linked ZnO micro rods by microwave radiation and its characterization is presented in this report. In this simple microwave assisted solution phase route zinc nitrate and hexamethylenetetramine has been used as the starting materials for the synthesis of linked ZnO rods. Linked ZnO rods with various morphologies such as bipods, tripods, tetrapods and etc have been prepared. The influence of irradiation time of microwave on the formation of linked ZnO rods was investigated. X-ray powder diffraction (XRD), field emission scanning electron microscopy (FESEM), and energy dispersive spectroscopy (EDS) were used for the characterization of the product. The FESEM images showed ZnO rods of diameter in the range of 100-200 nm and length around 5000 nm. (© 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

This report presents the results of the novel fabrication of 4H-SiC pillars with nanopores using ICP-RIE dry etching. Cl 2 /Ar gas plasma with various mass flow rates was used in this etching process to produce SiC nanopillars without using patterned etch mask. Cylindrical pillars of 300 nm diameter and 500 nm height with smooth side walls were etched on SiC wafer. The etching condition for the optimized fabrication of SiC nanopillars is presented in this report. Each nanopillar has been produced with a nanosize pore at the center along its length and up to the middle of the cylindrical nanopillar; it is a unique feature has not ever been reported in case of SiC. Inclusion of oxygen was found influence the formation of nanopillars by the effect of SiO 2 micro masking. The formation of self assembled SiO 2 layer and its micro masking effect in the fabrication of this unique nanostructure has been investigated using TEM, STEM and EDAX measurements.

Electrochemical deposition and characterization of CdSeTe thin film has been presented in this work. CdSexTe1−x (0 < x < 1) compound thin films have been electrodeposited cathodically on SnO2 conducting glass slides using various pH values and deposition potentials using an electrolyte bath solution consisting of CdSO4, SeO2 and TeO2 at different temperatures. The composition in the films has been found to vary linearly with the composition in the bath solution. The increase of selenium content ‘x’ in the CdSexTe1−x films has increased the band gap of the film. Photoelectrochemical solar cell studies were done and its response with concentration of Se was studied and these results have been discussed in this report. © 2010 Elsevier B.V. All rights reserved.

Zinc oxide (ZnO) thin films were grown onto SnO2 coated substrates by using cathodic electrodeposition with an aqueous zinc nitrate (Zn (NO3)2) solution at dierent bath temperatures. The kinetics of the electrodeposition of ZnO films has been investigated in this work. The eects of solution concentrations, and temperature and the electrode potential on the growth of ZnO thin films were investigated. The eects of pH on the structural and characteristics of the ZnO films were also studied in order to establish the optimal growth conditions for electrodeposition of ZnO thin films.

A 94 GHz single balanced mixer in 3-dimension was successfully fabricated. The GaAs-based low loss transmission lines, dielectric-supported air-gapped microstrip lines (DAMLs), have been developed using surface micromachining technology, and the DAML-based hybrid ring coupler is successively fabricated. We have developed the high-performance 94 GHz single balanced active mixer using hybrid ring coupler with 70 nm gate length MHEMT. The mixer showed the conversion loss of 2.5 dB ~ 2.8 dB and isolation characteristics less than −30 dB, in the range of 93.65 GHz ~ 94.25 GHz. These results are the best performances demonstrated from a 94 GHz single balanced mixer utilizing GaAs-based HEMTs in terms of conversion loss as well as isolation characteristics.

We developed the improved fabrication technology using the trench method for a graded-gap injector GaAs Gunn diode to avoid the formation of cracks which are caused by the difference in the thermal expansion coefficients between the GaAs epi-layer and the gold integral heat sink. We observed the negative-differential-resistance in the fabricated Gunn diode. The process we developed facilitates further process and handling because of the integral heat sink with thickness of 60 mum. Also, the formation of cracks in GaAs epi-layer was reduced during ohmic alloy process because of the reduced stress between the epi-wafer and the gold integral heat sink.

We have designed and fabricated a low LO power V-band CPW mixer using GaAs PHEMT technology for the application of millimeter-wave wireless communication systems. The mixer was designed using a unique gate mixing architecture to achieve simultaneously a low LO input power, a high conversion gain, and good LO-RF isolation characteristics. The V-band mixer was fabricated using the MIMIC process including 0.1-? GaAs PHEMTs and CPW transmission lines. The V-band mixer exhibited a high conversion gain of 2 dB at a low LO power of 0 dBm. The low LO power and the high conversion gain achieved in this work is among the best ever reported for a V-band mixer.

We introduce an all-inorganic solution processed bipolar nonvolatile resistive memory device with quantum dot/metal-metal oxide/quantum dot structure. The two terminal device exhibits excellent switching characteristics with ON/OFF ratio >103. The device maintained its state even after removal of the bias voltage. The switching time is faster than 50 ns. Device did not show degradation after 1-h retention test at 150 °C. The memory functionality was consistent even after multiple cycles of operation and the device is reproducible. The switching mechanism is discussed on the basis of charge trapping in quantum dots with metal oxide serving as the barrier.