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To obtain high transparecy conductive films (TCFs), graphene embedded indium tin oxide (ITO) TCFs (ITO-graphene-ITO) were formed (I-G-I), using ITO sputtering, and the exfoliation/transfer process of chemical vapor deposition (CVD) grown graphene. Compared with ITO-graphene (I-G), I-G-I TCFs showed degradation in transmittance, and in figure of merits(FOM) despite enhanced conductivity. After annealing, both transmittance and conductivity improved; however, were not dependent on the embedded graphene multilayers in the I-G-I structure. From the Raman spectra results, it was possible to investigate degradation of the graphene layers' 2D structures, caused by sputtering damage which occurred during the deposition of ITO onto the I-G structure. [ABSTRACT FROM AUTHOR]

For the direct formation of two-dimensional (2D) tungsten disulfide (WS2) thin films with higher productivity and lower process temperature than conventional chemical vapor deposition (CVD), WS2 thin films were deposited on a sapphire glass substrate by direct current (DC) sputtering and subsequent rapid thermal processing (RTP). From the optical investigation by atomic force microscopy (AFM), it was possible to stable surface and observe more improvements at higher RTP temperatures irrespective of sputtering power. Hall measurements showed higher resistivity and lower carrier density at higher DC sputtering power in spite of the constant carrier mobility. Raman spectrum results showed lateral vibration of tungsten and sulfur atoms at temperatures above 700 °C. The directly formed WS2 thin films showed the improvements in structural and electrical characteristics as a semiconductor layer. [ABSTRACT FROM AUTHOR]

For the realization of high conductive and transparent electrodes on flexible substrates, indium tin oxide(ITO), Ag, and ITO were sequentially deposited on polyethylene terephthalate(PET) and a Q-switched Nd:YVO4laser was used for direct etching of the ITO–Ag-ITO films. Considering the complementary relationship between transmittance and conductivity, Ag was deposited for different sputtering times and the laser etched results were also compared and analyzed. Considering the laser etched shape, the ITO–Ag-ITO electrodes were patterned with the optimized laser beam condition. From the current-voltage characteristics and multi-meter measurement, much lower resistances were obtained from electrically isolated ITO-Ag-ITO electrode. [ABSTRACT FROM PUBLISHER]

Nb2O5films were deposited with pulsed DC magnetron sputter which is versatile and provides the ability to deposit thin film of oxide compounds with high deposition rate. Current measurement data from the metal-insulator-semiconductor (MIS) structure followed Schottky emission mechanism andreverse current characteristics were analyzed with oxygen flow rate variation. Low frequency noise measurements have been carried out with MIS samples at the forward conduction region. The experimental noise data have been successfully explained by the random walk model. The effect of O2flow rate of deposition process on low frequency noise has also been investigated and analyzed. [ABSTRACT FROM AUTHOR]

Indium tin oxide (ITO) films were deposited on glass substrates by in-line DC sputtering and were annealed at different temperatures in the main chamber of sputter. The post-annealing effects on the optical and electrical properties of the ITO films were investigated and analyzed by various measurement systems. The results show that a higher annealing temperature makes an improvement on the electro-optical properties of the ITO films. The resistivity of the ITO films was reduced from 8.90×10−4Ω·cm to 2.91×10−4Ω·cm and the transmittance was increased from about 76.91% to 82.15% after post annealing at 300 °C in vacuum. The post annealed ITO glass was used in the fabrication of resistive touch panel and it was possible to obtain the better linearity characteristics than those from the touch panel fabricated with non-annealed ITO glass. [ABSTRACT FROM AUTHOR]

In the fabrication of zinc oxide thin film transistor(ZnO TFT), aluminum oxide(Al2O3) was deposited as gate insulator by using an oxygen atom neutral beam assisted deposition(NBAD) during e-beam evaporation. From the thickness of the Al2O3 layer evaporated with the oxygen NBAD process and the C-f measurement of metal-insulator-metal(MIM) capacitors fabricated with the NBAD Al2O3 layer, it was possible to conclude that the NBAD Al2O3 layer has a higher thickness and a higher dielectric constant at an acceleration beam energy of 300 eV as a result of the additional deposition of oxygen atoms during e-beam evaporation. The fabricated ZnO TFT with the NBAD Al2O3 gate insulator showed better electrical characteristics, such as a lower subthreshold swing and a higher on-off ratio, than those without any NBAD process. [ABSTRACT FROM PUBLISHER]

In this paper we have studied a low-temperature process of fabricating zinc oxide (ZnO) thin-film transistors (TFTs) on polyethylene terephthlate (PET) substrate. PET film has a lower glass transition temperature (Tg = 120°C) than costly Polyethersulphone (PES) film (Tg = 230°C). Therefore we applied a low-temperature cross-linked poly-vinylphenol (c-PVP) process to annealing at 110°C instead of the conventional c-PVP process (annealing at 165°C). The resulting TFTs based on oxide fabricated by the low-temperature process were similar in electrical characteristics to conventional TFTs. In addition, the ZnO TFTs fabricated by the low-temperature process exhibited a field-effect mobility of 0.075 cm2/Vs, a threshold voltage of 15 V and an on/off ratio of 1.7 × 105 respectively. [ABSTRACT FROM PUBLISHER]

A cold cathode fluorescent lamp (CCFL) and various color spectrum filters were used in the investigation of photoelectric characteristics of hydrogenated amorphous silicon thin film transistor(a-Si:H TFT). From the photo leakage currents of a-Si:H TFT for the transmitted backlights through the various color spectrum filters, it was possible to conclude the photo leakage currents are not directly related to the luminance of the transmitted backlights. The photoelectric characteristics were well described in terms of photon energy spectrums calculated from the photon energy and the energy transmittance of backlight through the color spectrum filters. [ABSTRACT FROM AUTHOR]

In the fabrication of transparent conductive oxide thin film transistor (TFT), an atomic layer deposited (ALD) zinc oxide (ZnO) and a cross-linked poly-vinyl-alcohol (c-PVA) were each used as active layer and gate insulating layer on poly-ethylene (PET) substrate respectively. Considering the transmittance and the deposition rate of the ALD ZnO at a low temperature without any damage on PET substrate, the ZnO layer was deposited at a temperature of 120°C on a spin-coated c-PVA layer. From the atomic force microscope (AFM) images, it was possible to conclude that the surface morphologies of ZnO deposited on a c-PVA layer was not inferior to those of ZnO deposited on bare-Si and that the c-PVA can be used as a gate insulator at 120°C. The fabricated ZnO TFT showed good electrical characteristics such as the mobility of 0.1 cm2/V · s, on-off current ratio of 4.5 × 104. [ABSTRACT FROM AUTHOR]