High Crystalline Cu2O Thin Films Prepared by Electric Current Heating Using Copper Wire

Cu wires were heated by electric currents to fabricate Cu2O thin films. The films were successfully deposited on glass substrates placed above the wires at air pressures in the range of 100 - 40 Pa. Then the films were annealed in a controlled atmosphere and investigated the crystallinity, morphology and the time response to illumination of the films. After annealing at 800 °C at atmospheric pressure with oxygen partial pressure of 12 Pa, the crystallinity was increased and the time response of photoconduction was successfully improved.

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Effect of Oxygen Partial Pressure on the Electrical and Optical Properties of DC Magnetron Sputtered AmorphousTiO2Films

Journal of Spectroscopy ◽

10.1155/2013/462734 ◽

2013 ◽

Vol 2013 ◽

pp. 1-7 ◽

Cited By ~ 7

Author(s):

M. Chandra Sekhar ◽

P. Kondaiah ◽

B. Radha Krishna ◽

S. Uthanna

Keyword(s):

Thin Films ◽

Optical Properties ◽

Oxygen Partial Pressure ◽

Partial Pressure ◽

Optical Transmittance ◽

Electrical And Optical Properties ◽

Glass Substrates ◽

Schottky Effect ◽

Partial Pressures ◽

Effect Of Oxygen

Titanium dioxide (TiO2) thin films were deposited on p-Si (100) and Corning glass substrates held at room temperature by DC magnetron sputtering at different oxygen partial pressures in the range9×10−3–9×10−2 Pa. The influence of oxygen partial pressure on the structural, electrical, and optical properties of the deposited films was systematically studied. XPS studies confirmed that the film formed at an oxygen partial pressure of6×10−2 Pa was nearly stoichiometric. TiO2films formed at all oxygen partial pressures were X-ray amorphous. The optical transmittance gradually increased and the absorption edge shifted towards shorter wavelengths with the increase of oxygen partial pressure. Thin film capacitors with configuration of Al/TiO2/p-Si have been fabricated. The results showed that the leakage current density of films formed decreased with the increase of oxygen partial pressure to6×10−2Pa owing to the decrease in the oxygen defects in the films thereafter it was increased. The current transport mechanism in the TiO2thin films is shown to be Schottky effect and Fowler-Nordheim tunnelling currents.

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Structural and Optical Properties of ZnO1-xSx Thin Films Grown by Pulse Laser Deposition on Glass Substrates

Materials Science Forum ◽

10.4028/www.scientific.net/msf.787.18 ◽

2014 ◽

Vol 787 ◽

pp. 18-22

Author(s):

Lei Zhang ◽

Liang Heng Wang ◽

Ming Kai Li ◽

Xun Zhong Shang ◽

Yun Bin He

Keyword(s):

Thin Films ◽

Oxygen Partial Pressure ◽

Partial Pressure ◽

Band Gap ◽

Transparent Conducting Oxide ◽

Optoelectronic Devices ◽

Ultra Violet ◽

Laser Deposition ◽

Visible Range ◽

Glass Substrates

With a wide band gap of 3.4 eV and a large exciton binding energy of 60 meV at room temperature, ZnO is attractive for blue and ultra-violet optoelectronic devices, and transparent conducting oxide films for photovoltaic applications. For a semiconductor to be useful, particularly in reference to optoelectronic devices, band gap engineering is of great importance in device development. Alloying of MgO and CdO with ZnO has been studied extensively in comparison to other ZnO alloys incorporating equivalent anions like ZnO1-xSx (ZnOS). In this work, high-quality ZnOS thin films were grown on glass substrates by pulsed laser deposition using a ZnS ceramic target with varying O2 partial pressures between 0 and 6 Pa. ZnOS alloys with a wurtzite structure were achieved and no evident phase separation was observed in the whole composition range as determined by X-ray diffraction. The optical transmission measurements show that the average transmittance in the visible range of the films is about 80%. The absorption edges of the films first shift towards low-energy side with increasing the oxygen partial pressure and then blueshift when the oxygen partial pressure is over 2 Pa. The bandgap energies of the ZnOS films were calculated to change from 3.06 to 3.72 eV, showing a nonlinear variation with a bowing behavior that was previously reported.

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