Influence Of Oxygen Flow Research Articles

Influence of Oxygen Flow on Structural, Optical, and Electrical Properties of Al:SnO2 Films Deposited at Room Temperature

Influence of Oxygen Flow on Structural, Optical, and Electrical Properties of Al:SnO2 Films Deposited at Room Temperature

Systematic Study of O2 Supply in Li–O2 Batteries with High and Low Doner Number Solvents

The Li–O2 battery is a promising technology due to its high theoretical specific energy. However, its practical capacity and cycling performance need further improvement. In this scenario, the influence of the electrolyte and the supply of air/O2 to the device are essential to enhance the performance and build a commercial prototype. This paper presents a study focusing on the influence of oxygen flow and pressure in the gravimetric capacity of Li–O2 batteries using two different electrolytes: dimethyl sulfoxide (DMSO/LiClO4) and tetraethylene glycol dimethyl ether (TEGDME/LiClO4). This study pointed out the negative influence of flow over the capacity when combined in an open cell. Due to electrolyte loss, the life cycle was also deeply affected using the open cell, especially for DMSO. However, DMSO leads to the best performance due to higher ionic conductivity, oxygen diffusivity, and absence of a direct reaction with the lithium anode. Thus, the closed cell reached a maximum discharge capacity of 22537 mAh g–1 with 26 cycles of 1000 mAh g–1 for DMSO and 8764 mAh g–1 with 13 cycles of 1000 mAh g–1 for TEGDME.

Influence of thickness and deposition angle on structural and optical properties of manganese oxide thin films

Manganese oxide thin films were produced on glass substrates by resistive evaporation at room temperature. The layers with different thickness (30 and 90 nm) at different deposition angles (0 and 40°) were prepared by electron gun evaporation method under ultra-high vacuum condition. After deposition of pure manganese oxide thin films a post-annealing process was used in a uniform oxygen flow of 300 (sccm) and at 500 K annealing temperature. Optical transmittance and reflectance of the layers were measured in the wavelength of 350–850 nm by a spectrophotometer. Kramers–Kronig relations were used to calculate the optical constants. The influence of oxygen flow and annealing temperature on optical properties is investigated. It was found that film thickness and deposition angle plays a significant role on the nanostructures as well as optical properties of layers and cause major variations in behavior of thin manganese oxide films. The physical properties of materials were characterized by X-ray diffraction (XRD), FE-SEM, AFM, EDAX, and UV-VIS techniques.

Influence of oxygen flow during sputtering process on the electrical properties of Ga-doped InZnSnO thin film transistor

This work presents the electrical properties of amorphous gallium-doped indium zinc tin oxide (Ga-IZTO) thin film transistors (TFTs), as a function of O2 flow rate (Ar/O2), during the sputtering process of the channel layer. As the O2 flow rate increased from 30:0 to 30:7, the saturation mobility ( SAT) monotonically degraded from 31.5 cm2V−1s−1 to 12.0 cm2V−1s−1, the threshold voltage (V TH) shifted from 0.8 V to 6.8 V, and the V TH shift (ΔV TH) induced by the negative bias stress improved from −7.0 V to −2.8 V. X-ray diffraction analysis indicated that themicrostructure of all the films is amorphous, which is independent of O2 flow rate. Transmittance spectra reflected that the average transmittance of the thin film is sensitive to the O2 flow rate and decreases as the O2 flow rate increases. XPS analysis revealed that the density of oxygen vacancies is reduced, and the oxygen lattices are enhanced as the O2 flow rate increases. The Hall effect measurements indicated that the carrier concentration (n) was reduced with increasing O2 flow rate. These results show that the electrical properties of Ga-IZTO TFTs can be easily tuned by the O2 flow rate during the sputtering process. The related mechanism for the variations of electrical properties of Ga-IZTO TFT has been discussed in detail.

Effects of oxygen flow velocity on the sintering properties of ITO targets

Due to the considerable influence of oxygen flow on the resistivity and transmittance of ITO films, the study on the effects of oxygen flow velocity on the sintering properties of ITO targets has a positive role in promoting their use in large output industries. In the work, ITO targets of three sintering conditions were used to reveal the action mechanism of oxygen flow velocity on the phase and elemental composition, micro-morphology, density, mass loss ratio, oxide content, resistivity and elemental chemical states by XRD, BSE, EPMA, SEM, XRF and XPS et al. ITO target sintered under oxygen flow velocity of 10 L/min owns super high relative density of 99.83%, mass loss ratio of 1.417% and the minimum resistivity of 1.583 × 10−4 Ω·cm. It can conclude that the increase of oxygen flow velocity can increase the oxygen pressure within the sintering furnace, which can influence the mass transport mechanism throughout the whole sintering process, improve the density of ITO targets, and decrease the InO formation of the target interior as a result of maintaining the mass content ratio of indium to tin and decreasing the resistivity of ITO targets.

Influence of oxygen flow and film thickness on the texture and microstructure of sputtered ceria thin films

An in depth understanding of the influence of the deposition parameters on the texture and microstructure of sputtered ceria thin films could pave the way towards the optimization of doped ceria thin films to be applied as fuel cell related electrolytes. In this work, ceria thin films were deposited at constant current using DC reactive magnetron sputtering. The influence of the oxygen flow and the film thickness on the crystallographic orientation and microstructure was studied. 200nm thick films exhibit a change in out-of-plane orientation from random to preferential that coincides with the transition from metallic to poisoned mode. The preferential out-of-plane orientation of the films deposited in metallic mode changes from random to [200] as a function of both thickness and oxygen flow. Hence, films deposited in this mode are identified as grown under zone T conditions which agrees with scanning electron microscopy cross sections. In poisoned mode, however, a second transition is observed. The films deposited in this mode grow in zone II, but once more a change in out-of-plane orientation from [200] to random occurs when the oxygen flow is increased to higher values.

Dependence of electrical and optical properties of IGZO films on oxygen flow

Amorphous InGaZnO (a-IGZO) films were deposited on the corning eagle XG (EXG) glass substrates using magnetron sputtering method. The structure, surface morphology, electrical and optical properties of these films were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), semiconductor parameter analyzer and spectrophotometry, respectively. The influence of oxygen flow on the electrical properties of IGZO thin films was studied, showing that increasing oxygen flow changes the resistivity with six orders of magnitude. The contact resistance of ITO/IGZO is 7.35×10−2 Ω·cm2, which suggests that a good ohmic contact exists between In2O3: Sn (ITO) and IGZO film.

Emission and structure investigations of Si nano-crystals embedded in amorphous silicon

The influence of oxygen flow at the hot-wire-CVD process on light-emission and structural properties of Si nano-crystallites embedded in amorphous silicon has been investigated. It was shown that increasing of an oxygen flow is accompanied by the Si nanocrystallite size variation and by the appearance of some new photoluminescence bands. Using of X-ray diffraction and photoluminescence methods the dependence of photoluminescence properties on the size of Si nanocrystallites was shown. The nature of light emission centers is discussed as well.

Correlation between structure, stress and deposition parameters in direct current sputtered zinc oxide films

Thin ZnO and ZnO:Al films have been prepared by reactive dc magnetron sputtering, using both metallic and ceramic targets. The influence of oxygen flow and total pressure on film stress, structure, texture, and surface roughness has been examined. The properties of the films strongly depend on the deposition conditions, in particular the total pressure. Increasing the pressure from 0.5 to 2 Pa resulted in rougher, and less strained films. Increasing the oxygen flow at a constant total pressure led to a slight increase in stress, but had no visible effect on the surface roughness. Structural investigations by x-ray diffraction (XRD) showed that polycrystalline films with pronounced preferential orientation were formed. Most XRD-spectra showed a coexistence of strained and unstrained ZnO in wurtzite structure. The relative abundance of the relaxed phase is a function of the intrinsic stress only, and does not directly depend on deposition parameters. However, the deposition parameters determine the stress within the film, and thus influence the amount of the relaxed grains.

Influence of oxygen flow on crystallization and morphology of PLZT thin films

PLZT thin films were prepared by a dip coating process using Pechini's method, also known as polymeric precursor method. The PLZT solution was obtained from a mixture of the individual cation solutions and the process to prepare each solution is based on metallic citrate polymerization. The viscosity of the PLZT solution was adjusted at 40 cP while the ionic concentration was adjusted at 0.1 M. PLZT solutions were deposited on silicon (100) and platinum coated silicon (100) substrates with withdrawal speed at 5 mm/min. The coated substrates were thermally treated with a heating rate of 1 °C/min up to 300 °C and 5 °C/min up to 650 °C in order to obtain homogeneous and cracks free films. The influence of oxygen flow on crystallization and morphology of PLZT (9/65/35) thin film is discussed.

Influence of Oxygen Flow on Crystallization and Morphology of LiNbO 3 Thin Films

Polymeric precursor solution (Pechini method) was used to deposit LiNbO 3 thin films by spin-coating on (100) silicon substrates. X-ray diffraction data of thin films showed that the increase of oxygen flow promotes a preferred orientation of (001) LiNbO 3 planes parallel to the substrate surface. Surface roughness and grain size, observed by atomic force microscopy, change also with oxygen flow.

Influence of Oxygen Flow on Crystallization and Morphology of LiNbO 3 Thin Films

Polymeric precursor solution (Pechini method) was used to deposit LiNbO 3 thin films by spin-coating on (100) silicon substrates. X-ray diffraction data of thin films showed that the increase of oxygen flow promotes a preferred orientation of (001) LiNbO 3 planes parallel to the substrate surface. Surface roughness and grain size, observed by atomic force microscopy, change also with oxygen flow.