The sprayed ZnO films: nanostructures and physical parameters

We synthesized the pure and indium-doped （IZO） ZnO films with a facile composition control spray pyrolysis route. The substrate temperature （Ts） and In-doping effects on the properties of as-grown films are inves- tigated. The X-ray pattern confirms that the as-synthesized ZnO phase is grown along a （002） preferential plane. It is revealed that the crystalline structure is improved with a substrate temperature of 350 ℃ Moreover, the morphol- ogy of as-grown films, analyzed by AFM, shows nanostructures that have grown along the c-axis. The （3 ×3 μm2） area scanned AFM surface studies give the smooth film surface RMS 〈 40 nm. The UV-VIS-IR measurements reveal that the sprayed films are highly transparent in the visible and IR bands. The photoluminescence analysis shows that the strong blue and yellow luminescences of 2.11 and 2.81 eV are emitted from ZnO and IZO films with a slight shift in photon energy caused by In-doping. The band gap is a bit widened by In-doping, 3.21 eV （ZnO） and 3.31 eV （IZO） and the resistivity is reduced from 385 to 8Ω·m. An interesting result is the resistivity linear dependence on the substrate temperature of pure ZnO films.

The investigation of electrodeposited Cu_2O/ITO layers by chronocoulometry process:effect of electrical potential

The thin films of Cu2O are deposited by electrodeposition technique onto indium tin oxide（ITO）-coated glass substrate at different potentials. The precursor is an aqueous solution which contains respectively 0.05 M of CuSO4 and citric acid at kept temperature of 60℃ and the applied potential varies within the {-0：4 V,-0：7 V}SCE range. Based on the chronocoulometry（CC） process, the electrochemical, structural and optical parameters are determined. We measured the current as function of potential within the {-0：4 V,-0：7 V} range and the higher current is found to be within the {-0：7 V,-0：3 V} band. The grain sizes are of 12.12 nm and 35.47 nm according to（110） and（221） orientations respectively. The high textural coefficient of 0.943 is recorded for the potential -0：7 V.The transmittance of 72.25 %, within the visible band, is obtained for the as-grown layer at -0：4 V and the band gap is found to be 2.2 e V for the electrodeposition potential of -0：7 V.

Fabrication of a novel MOS diode by indium incorporation control for microelectronic applications

Control of the electronic parameters on a novel metal–oxide–semiconductor（MOS）diode by indium doping incorporation is emphasized and investigated.The electronic parameters,such as ideality factor,barrier height（BH）,series resistance,and charge carrier density are extracted from the current–voltage（I–V）and the capacitance–voltage（C–V）characteristics.The properties of the MOS diode based on 4%,6% and 8% indium doped tin oxide are largely studied.The Ag/SnO2/nSi/Au MOS diode is fabricated by spray pyrolysis route,at 300℃ from the In-doped SnO2layer.This was grown onto n-type silicon and metallic（Au）contacts which were made by thermal evaporation under a vacuum@10^-5 Torr and having a thickness of 120 nm and a diameter of 1 mm.Determined by the Cheung-Cheung approximation method,the series resistance increases（334–534Ω）with the In doping level while the barrier height（BH）remains constant around 0.57 V.The Norde calculation technique gives a similar BH value of 0.69 V but the series resistance reaches higher values of 5500Ω.The indium doping level influences on the characteristics of Ag/SnO2：In/Si/Au MOS diode while the 4% indium level causes the capacitance inversion and the device turns into p-type material.

Organic–inorganic Au/PVP/ZnO/Si/Al semiconductor heterojunction characteristics

The paper reports the fabrication and characterization of a novel Au/PVP/ZnO/Si/Al semiconductor heterojunction（HJ） diode. Both inorganic n type ZnO and organic polyvinyl pyrrolidone（PVP） layers have grown by sol-gel spin-coating route at 2000 rpm. The front and back metallic contacts are thermally evaporated in a vacuum at pressure of 10^-6 Torr having a diameter of 1.5 mm and a thickness of 250 nm. The detailed analysis of the forward and reverse bias current-voltage characteristics has been provided. Consequently, many electronic parameters, such as ideality factor, rectification coefficient, carrier concentration, series resistance, are then extracted.Based upon our results a non-ideal diode behavior is revealed and ideality factor exceeds the unity（n 〉 4）. A high rectifying（-4.6 × 10^4） device is demonstrated. According to Cheung-Cheung and Norde calculation models, the barrier height and series resitance are respectively of 0.57 eV and 30 kΩ. Ohmic and space charge limited current（SCLC） conduction mechanisms are demonstrated. Such devices will find applications as solar cell, photodiode and photoconductor.