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Aluminum and indium codoping zinc oxide (AIZO) films have been deposited simultaneously on polyethylene terephthalate (PET) substrate by radio frequency (RF) magnetron sputtering technique at room temperature (from a ceramic target) prepared with a mixture of zinc oxide (ZnO), aluminum (Al), and indium oxide (In2O3) of varying RF power range from 50 to 100 W and working pressure range from 2.5 to 15 mTorr. In order to obtain an acceptable performance rate with high-quality conducting thin films, the effect of correlation between the electrical, optical, and microstructural properties was investigated. The electrical resistivity significantly declined, and the carrier concentration improved as a result of In2O3 and Al incorporation within the ZnO and the increasing RF power. In this case, the best optical and electrical results were deposited at the RF power of 100 W with the working pressure of 2.5 mTorr. We were practicable to fabricate AIZO/PET electrodes of the lowest resistivity ( $7.6\times 10^{-3}\,\Omega $ -cm), the highest mobility, carrier concentration ( $8.29\times 10^{3}$ cm2/vs and $9.8\times 10^{20}$ cm−3, respectively), and the maximum transmittance (83%–96%) along an energy bandgap range of 3.3–3.65 eV with a well crystalline structure showing a roughness surface of the AIZO films and a suitable Herzberg–Teller (HT). Thus, according to these expressions, we could be responsible for preparing AIZO/PET with improved electrical property and microstructure of great applications for flexible electronic devices.

This paper presents the charge and discharge combination of the supercapacitors and the AC power source in storing and supplying energy for computer backup power. According to the behavior of storing and supplying energy, the SC can be charged with high currents. Whereas the battery cannot. The supercapacitors efficiency in storing and supplying power at high voltage and low current is 95.20%. An analysis also revealed that the charging time of the supercapacitors is less than 199 s. The combination of the supercapacitors and the battery required 604 s for charging time. The battery alone is the longest at 1080 s. Moreover, the study showed that the discharging time of the supercapacitors and the battery combination was more than 610 s. The discharging time of the battery and the supercapacitors were 285 and 579 s, respectively. Therefore, the combination of the supercapacitors and an AC power source can replace battery in the design of computer backup.

Thin films of indium zinc oxide (IZO) were deposited on polyethylene terephthalate (PET) substrate with varying plasma power (from 100 W to 300 W) using the radio-frequency (RF) magnetron sputtering technique and electroluminescence (EL) devices. The IZO films that were obtained from this process were treated with oxygen plasma powers using the plasma-enhanced chemical vapor deposition (PECVD) system. After this treatment, the microstructural, electrical, and optical properties of IZO films were observed and reported. The result showed that the IZO/PET films was fabricated at the lowest resistivity ( 2.83 × 10 − 3 Ω · cm ), while the optical characterization displayed the maximum transmittance of 95% in the visible region with a smooth morphology and good crystalline structured, affected by the 300 W of plasma power with the optimum carrier concentration ( 4.93 × 10 21 c m − 3 ) and hall mobility (42.12 cm2/V·sec), respectively. The luminance properties and the EL efficiency were also investigated and shown a 300 W highest point of plasma power with 84 cd/m2 and 0.924 lm/W. The film properties were found responsible for producing and improving the performance of IZO/PET substrate, suitable for displaying the devices.

Three-dimensional (3D) nanostructure electrode based on the transparent conductive oxide (TCO) is an alternative and effective approach for increasing the performance of next-generation photovoltaic and optoelectronic devices. In this work, we prepared the vertically aligned indium tin oxide nanorods (ITO-NRs) film on silicon (100) wafer and commercial ITO thin-film coated glass substrate (ITO-TF/glass) by the glancing angle deposition (GLAD) technique. The morphologies of the ITO-NRs films were confirmed by field-emission scanning electron microscope (FE-SEM). The grazing-incident X-ray diffraction (GIXRD) observed that the ITO-NRs were formed as amorphous and nanocrystalline phase. The photoemission spectra revealed the atomic percentage of elements in ITO-NRs, and the work function of the ITO-NRs was found to increase as a function of layer thickness. To simply demonstrate their feasibility in TCO applications, the ITO-NRs films were deposited on ITO-TF/glass. We found that the resistivity of ITO-NRs on ITO-TF/glass was higher than that of a bare ITO-TF/glass substrate, which can explain through the surface recombination loss. Besides, by precisely tunning the layer thickness of ITO-NRs films, the optical transmittance was enhanced at 85.5–90.0% over the broad wavelength in the visible region with omnidirectional AR characteristic which is superior to that in conventional ITO-TF/glass. Our thickness dependence of the ITO-NRs properties discloses promising 3D TCO nanostructure in wide application.

Growths of the indium tin oxide (ITO) nanorod films have been demonstrated by ion-assisted electron-beam evaporation with the glancing-angle deposition technique based on variation in deposition rate. Investigations have been performed on nanostructured ITO films deposited on ITO-coated commercial substrates in comparison to bare substrates. The physical microstructures have been investigated by grazing-incident X-ray diffraction (GIXRD), field-emission scanning electron microscopy (FE-SEM), and high-resolution transmission electron microscopy (HR-TEM). The electrical, optical, and hydrophobic properties were characterized by four-point probe measurements, UV–Vis–NIR spectrophotometry with angle-dependent technique, and contact angle goniometry, respectively. The results indicated that physical morphologies and nanorod diameters of ITO nanorod films were heavily influenced, and thus could be controlled, by deposition rate. The primary reason was self-annealing effect which occurred during film deposition and was crucial factor towards surface diffusion and film crystallinity. From the optical examinations, ITO nanorods deposited on the ITO-coated glasses exhibited significant improvements on transparent conductive oxide (TCO) properties from reference samples. The proposed ITO materials could therefore function as omnidirectional anti-reflection materials and super hydrophobic surface. This work have also proved that the ITO nanorods prepared by the electron-beam evaporation with the GLAD technique was highly promising for solar cell and optoelectronic applications.

Indium doped tin oxide (ITO) nanostructured films were prepared by the electron-beam evaporation with the oblique-angle deposition (OAD) technique. The influence of the film thickness of the ITO nanostructures on the crystal structures, the physical morphologies, the optical properties, and the electrical attributes was investigated by grazing-incident X-ray diffraction (GIXRD), field-emission scanning electron microscopy (FE-SEM), UV-Vis spectrophotometry, four-point probe measurements, the respectively. The GIXRD analyses indicated that the ITO nanostructured films were mostly polycrystalline with the cubic bixbite structure. The FE-SEM micrographs clearly showed that the increased film thickness greatly affected the morphologies of the ITO nanostructures. The optical transmission spectra at the different angles of incidence clearly demonstrated the optimized results for the highest transmission in the visible region. The electrical resistivity of the ITO nanostructures was gradually decreased with the increased ITO thickness. Finally, the most optimized solar transmission with small light scattering and sheet resistance were discussed based on the anti-reflection performance of the ITO nanostructured films towards the solar cell applications.

In this study, we investigated the effects on the film thickness of the vertically aligned indium-doped tin oxide nanorods (ITO NRs). The ITO nanorods of deposited time at 180 to 780 sec were deposited on the silicon wafers and ITO-coated glass substrate by the ion-assisted electron-beam evaporation with the glancing-angle deposition technique. The physical microstructures and optical properties of the prepared samples have been investigated by grazing-incident X-ray diffraction (GIXRD), field-emission scanning electron microscopy (FE-SEM), and spectrophotometry. From the results, the ITO nanorods indicated the bixbite structures. The FE-SEM micrographs showed the changes of the physical morphologies based on the increased film thickness. The angle-dependent transmission as measured from -80° to 80° incident angles demonstrated the increased optical transmission from the vertically aligned ITO nanorods, compared to that of the ITO-coated glass. The enhancement of the optical transmission was related to the anti-reflection and light-scattering properties of the ITO nanorods, and offered a great potential for solar cell applications.

This paper describes the design charging and discharging supercapacitors of LED lamps for emergency lighting rated 10-W, 12-V. Designing two modules of supercapacitors used, each 33.33-F, 15-V. By SC1 and SC2 are charged by simultaneously until fully. When the power outage SC1 will discharging the led lamps until the voltage reduced to 5-V. Then SC2 will discharging charge to the led lamp until the voltage reduced to 5-V. Causing both SC1 and SC2 to not be able to discharge energy. When the electrical system enters normal conditions, both SC1 and SC2 will be recharged again. The results showed that was when supercapacitors charged by plugging in to the 220-Vac electrical system. The supercapacitors were fully charged at 15.4-V in 10 minutes. After that, the relay control circuit would disconnected the charging process. In case of power outage, the supercapacitors discharging to the LED lamps. It can give luminance for 28.34 minutes. The luminous efficacy of emergency lighting was 20.20 lumens per watt.

Solar cell converts sunlight into electricity with no moving parts and environmental friendly. Although silicon based solar cell is currently more efficient, the dye-sensitized solar cell is considerably cheaper to manufacture because of its low cost materials and simplicity process of fabrication. In this paper, the development of plasma formed equipment for thin film material on flexible solar cell using low-pressure high frequency Plasma Chemical Vapor Deposition method on the surface of Polyethylene naphthalate (PEN) with the mixture of Ar gas and N2gas is presented. The results indicate that using this method can be possible for surface modification.

Even though silicon based solar cell currently has more efficient, the dye sensitized solar cell is considerably cheaper for manufacturing because of its low cost materials and simplicity process of fabrication. In this paper, the development of plasma formed equipments for thin film material on flexible solar cell using low-pressure high-frequency plasma chemical vapor deposition method on the surface of Si wafer with the mixture of Ar gas and O 2 gas is presented. The results indicate that using this method can be possible for surface modification.

Electroluminescence (EL) device is a new technology; its thickness is within micrometer range which can bend more easily and emit light. However, the thickness of ZnS:Cu phosphor layer may affect the light intensity, so we have analyzed the thickness of ZnS:Cu phosphor layer on EL device. The EL devices consist of ITO:PET/ZnS:Cu phosphor/insulator (BaTiO3)/Ag electrode. The EL devices were fabricated in changing thickness 10 μm, 30 μm, and 50 μm. At 100 V 400 Hz, the luminance of EL devices was 51.22 cd/m2 for thickness 30 μm more than that of 45.78 cd/m2 (thickness: 10 μm) and 42.58 cd/m2 (thickness: 50 μm). However, the peak light intensity was achieved at wavelength of 507 nm which was not influenced by the thickness of the ZnS:Cu phosphor. The use of the ZnS:Cu phosphor layer at thickness 30 μm in the EL device significantly improves the luminescence performance.

This study deals with the performance analysis of off-grid solar photovoltaic electrification system for sustainable rural Information and Communication Technologies (ICTs) development located in 4 regions of Thailand. The local solar irradiation, module working temperature, mean sea level and ambient temperature are included to investigate the production of photovoltaic output power of the system different weather conditions over the year. The results can be used to provide manufacturers and researchers to develop their products and enhance the knowledge on the design of off-grid solar photovoltaic electrification system under the actual field conditions, respectively.

In recent years, a flexible type of solar cell that can maintain various shape changes and that is applicable to virtually all products has attracted global attention. In the present research, we describe equipment for the production of thin-film material for flexible type solar cells that uses a high-frequency plasma chemical vapor deposition (CVD) method. This equipment is now at the development stage, and in order to clarify the cardinal trait of the plasma, we performed a plasma treatment on the surface of a Si wafer. Using X-ray photoelectron spectroscopy and contact angle meter measurements, we identified one index that clarifies the simple cardinal trait of plasma CVD.

Electricity, Information and Communication Technologies (ICTs) are very important not only in urban areas but also in rural areas. To provide ICTs service in rural areas, sources of electricity and communication infrastructures must be implemented. Electricity is a major condition due to the fact that all electronic devices needed it in order to power on, so that it is impossible to operate any forms of ICTs in areas where the main national grid line is unavailable. Almost rural areas of Thailand where the main national grid line is unavaila ble have very good sunlight intensity. Photovoltaic is the most effective renewable energy technologies in those areas for meeting electricity needed in areas that are not connected to the main national grid line. In this paper, the efficiency utilization of photovoltaic as source of electricity for broadband satellite communication systems as well as social and economic impact and quality of life of people in rural areas of Thailand are pr esented. The results show that most rural communities would be able to universally access to the basic telecommunications services such as internet access and public telephone via satellite communication systems. However, in some field cas e study, broadband internet access via sa tellite communication may be unnecessary for some rural communities and the most exactly rural communities needed are electricity for household usage and battery charger. Keywords: photovoltaic, rural Thailand, broadband, satellite communications, ICT

Indium Tin Oxide (ITO) film is evaporated on the PEN film using MirrorTron Sputtering system, which is a new sputtering system enabling sputter deposition at a low temperature, separating a sputtering chamber and a deposition chamber. As a result, a uniform ITO thin-film deposition with a film thickness of 150 nm is enabled. This ITO thin-film is chemically analyzed using Focused ion beam and X-ray photoelectron spectroscopy. As a result, good thin-film condition is confirmed.

Questionnaire investigation is implemented to the college students in Thailand and Japan, concerning electric and energy. As a result, students in both countries understand well that electric and energy are related each other. However, there are many students in Thailand who never saw photovoltaic generation and wind-power generation. Difference in knowledge of energy among the students of same generation is clear, by crossing the border.