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"This book investigates the effect of sintering temperature on willemite based glass-ceramic doped with different content of Er2O3. It is the first to report research on producing willemite by using waste materials and using trivalent erbium (Er3+) as a dopant. This book provides a survey of the literature on glass and glass-ceramic, while comprehensive experiments and analysis have been performed on the material used. "

"Transparent conducting oxide (TCO) glasses play an important role invarious technology, including dye sensitized solar cells. One of the mostcommonly used glass is indium tin oxide (ITO) glass, which is expensive.Therefore, the mainpurpose of this research was to determine if ITO glass can be replaced withfluorine-doped tin oxide (FTO) glass,which is easier and more economic to manufacture. For this purpose, a tinchloride dehydrate (SnCl2.2H2O)precursor was doped with ammoniumfluoride (NH4F) using asol-gel method and spray pyrolysis technique toinvestigate the fabrication process for conductiveglass. NH4F wasdoped at a ratio of 2 wt% in the SnCl2.2H2O precursor atvarying deposition times (10, 20, and 30 minutes) and substrate temperatures(250, 300, and 350°C). Theresults revealed that longer deposition times created thicker glass layers withreduced electrical resistivity. The highest opticaltransmittance was 75.5% and the lowest resistivitywas 3.32´10-5 Ω.cm,obtained from FTO glasssubjected to a 20-minute deposition time at deposition temperature of 300oC."

"Transparent conducting oxide (TCO) glasses play an important role in various technology, including dye sensitized solar cells. One of the most commonly used glass is indium tin oxide (ITO) glass, which is expensive. Therefore, the main purpose of this research was to determine if ITO glass can be replaced with fluorine-doped tin oxide (FTO) glass, which is easier and more economic to manufacture. For this purpose, a tin chloride dehydrate (SnCl2.2H2O) precursor was doped with ammonium fluoride (NH4F) using a sol-gel method and spray pyrolysis technique to investigate the fabrication process for conductive glass. NH4F was doped at a ratio of 2 wt% in the SnCl2.2H2O precursor at varying deposition times (10, 20, and 30 minutes) and substrate temperatures (250, 300, and 350°C). The results revealed that longer deposition times created thicker glass layers with reduced electrical resistivity. The highest optical transmittance was 75.5% and the lowest resistivity was 3.32´10-5 ?.cm, obtained from FTO glass subjected to a 20-minute deposition time at deposition temperature of 300oC."

"Fluorine-doped tin oxide (FTO) is one of the conductive glasses that have strategic functions in various important applications, including dye-sensitized solar cell (DSSC). In the current work, the effects of deposition time (5, 10, 20, 30, and 40 minutes) upon the fabrication process of FTO thin film using spray pyrolysis technique with modified ultrasonic nebulizer has been studied in regard to its microstructural, optical, crystallinity, and resistivity characteristics. The variation was also performed by comparing the pure tin chloride precursor and the solution that was doped with fluor (F) at 2 wt% in order to see the doping effect on the properties of thin film. The thin films were characterized using x-ray diffraction (XRD), scanning electron microscope (SEM), ultraviolet-visible (UV-Vis) spectroscopy, and digital multimeter. On the basis of current investigation, it has been found that the best FTO was obtained through the pyrolysis technique of 20-minute deposition time, providing optical transmittance of 74%, a band gap energy (Eg) of 3.85 eV and sheet resistance (Rs) of 7.99 Ω/sq. The fabricated FTO in the present work is promising for further development as conducting glass for dye-sensitized solar cell (DSSC)."

"Fluorine-doped tin oxide (FTO) is one of the conductive glasses that have strategic functions in various important applications, including dye-sensitized solar cell (DSSC). In the current work, the effects of deposition time (5, 10, 20, 30, and 40 minutes) upon the fabrication process of FTO thin film using spray pyrolysis technique with modified ultrasonic nebulizer has been studied in regard to its microstructural, optical, crystallinity, and resistivity characteristics. The variation was also performed by comparing the pure tin chloride precursor and the solution that was doped with fluor (F) at 2 wt% in order to see the doping effect on the properties of thin film. The thin films were characterized using x-ray diffraction (XRD), scanning electron microscope (SEM), ultraviolet-visible (UV-Vis) spectroscopy, and digital multimeter. On the basis of current investigation, it has been found that the best FTO was obtained through the pyrolysis technique of 20-minute deposition time, providing optical transmittance of 74%, a band gap energy (Eg) of 3.85 eV and sheet resistance (Rs) of 7.99 ?/sq. The fabricated FTO in the present work is promising for further development as conducting glass for dye-sensitized solar cell (DSSC)."

"Lapisan Zinc oxide dideposisikan diatas substrat silikon (Si) dan Indium Tin Oxide (ITO) menggunakan metode spin-coating. Prekursor yang dipilih adalah Zinc Acetate Dihydrate yang dilarutkan dalam 3 jenis pelarut yang berbeda-beda yaitu etilen glikol, aqua bides, dan aqua bides - etilen glikol. Setelah pendeposisian pada 2000 rpm selama 20 detik, lapisan diberi perlakuan panas yaitu drying pada 100°C dan suhu annealing pada temperature 500°C untuk membentuk 5 lapis ZnO dari setiap sampel. Hasil dari pengujian X-Ray diffraction (XRD) dari sampel lapisan dengan 3 jenis larutan yang berbeda menunjukkan hasil struktur kristal yang sama yaitu heksagonal dengan parameter kisi yang berbeda-beda untuk setiap jenis pelarut dengan parameter kisi a=b≠c, namun berbeda nilai parameter untuk setiap pelarut berbeda. Sifat optis diinvestigasi dengan Uv-visible diffuse reflectance, dan energi band gap didapatkan. Hasil dari scanning electron microscopy (SEM) menginvestigasi morfologi lapisan dari pelarut yang berbeda. Sintesis dengan berbeda-beda pelarut menunjukkan pengaruh pada struktur dan sifat optis dari lapisan ZnO.

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Zinc oxide Films were deposited on the substrate Silicon (Si) and Indium Tin Oxide (ITO) with a spin-coating method. Preferred precursor was Zinc Acetate Dihydrate dissolved in three different solvents ethylene glycol, aqua bidest, and aqua bidest - ethylene glycol. After deposited at 2000 rpm for 20 seconds, the films were dried at 100°C and annealed at 500°C in furnace for five layers each samples.

Results of X-ray diffraction (XRD) of 3 solvents showed the same crystal structure which was hexagonal, with lattice parameters a = b ≠ c were different for each solvent. Optical properties was investigated with Uv-visible diffuse reflectance, and so the band gap energy was achieved The results of scanning electron microscopy (SEM) investigated the morphology thin films of"

"Transparent conductive oxide (TCO) glass is one of most important components in dye-sensitized solar cell (DSSC) device. In addition to its high electrical conductivity, transparency is another important requirement that must be achieved in fabricating TCO. One TCO film is fluorine-doped tin oxide (FTO), which can be considered as the most promising substitution for indium-doped tin oxide (ITO), since the latter is very expensive. However, the fabrication techniques for TCO film need to be carefully selected; the synthesis parameters must be properly optimized to provide the desired properties. In this work, FTO glass has been fabricated by the ultrasonic spray pyrolisis technique with different precursors, i.e. tin (II) chloride dihydrate (SnCl2.2H2O) and anhydrous tin (IV) chloride (SnCl4), as well as different solvents, i.e. ethanol and methanol. For both conditions, ammonium fluoride (NH4F) was used as the doping compound. The resulting thin films were characterized by use of a scanning electron microscope (SEM), x-ray diffraction (XRD), ultraviolet-visible (UV-Vis) spectroscopy and a four-point probe test. The results of the investigation show that the highest transmittance of 88.3% and the lowest electrical resistivity of 8.44×10-5 ?.cm were obtained with the FTO glass processed with 20 minutes of spray pyrolysis deposition and 300oC substrate heating, using SnCl4 as the precursor and methanol as the solvent. It can be concluded that TCO fabrication with tin chloride precursors and ammonium fluoride doping using ultrasonic spray pyrolisis can be considered as a simple and low cost method, as well as a breakthrough in manufacturing conductive and transparent glass."

"Nanorod seng oksida (ZnO) berdopan tunggal Al, berdopan tunggal Mg, dan berdopan ganda Al-Mg ditumbuhkan di atas substrat kaca berlapis indium timah oksida (ITO) melalui dua tahap, yaitu deposisi lapisan benih dengan metode ultrasonic spray pyrolysis (USP) dan penumbuhan nanorod dengan metode hidrotermal. Pengamatan scanning electron microscopy (SEM) menunjukkan sebagian besar nanorod ZnO memiliki orientasi tegak lurus terhadap permukaan substrat dan pemetaan elemen dengan energy dispersive x-ray spectroscopy (EDS) menunjukkan seluruh elemen dopan tersebar merata di seluruh permukaan nanorod ZnO. Analisis difraksi sinar-x (XRD) menunjukkan bahwa pada nanorod ZnO berdopan Al, Mg, Al-Mg tidak terdapat fasa sekunder dan puncak bergeser ke sudut 2θ yang lebih besar karena adanya pembesaran volume kisi kristal. Spektrum UV-vis menunjukkan bahwa penambahan dopan tunggal Al atau Mg cenderung meningkatkan transparansi pada panjang gelombang cahaya tampak, sedangkan penambahan dopan Al pada nanorod ZnO berdopan ganda Al-Mg justru mengurangi transparansi. Perubahan energi celah pita akibat penambahan dopan Al dan/atau Mg masih belum memiliki pola yang jelas. Sedangkan hasil pengujian fotoluminesen (PL) menunjukkan semua nanorod ZnO memiliki banyak cacat alami kisi kristal.

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Al-doped, Mg-doped, and Al-Mg-doped zinc oxide (ZnO) nanorods were grown on indium tin oxide (ITO) coated glass substrates through two steps, i.e.seed layer deposition using ultrasonic spray pyrolysis (USP) method and nanorod growing using hydrothermal method. Scanning electron microscopy (SEM) imaging showed that most of the ZnO nanorods had the growth orientation perpendicular to the substrates surface and the element mapping undergone using energy dispersive x-ray spectroscopy (EDS) showed that all the doping elements were well distributed on the entire of the ZnO nanorod surfaces. XRD analysis results showed that Al-, Mg-, and Al-Mg- doped ZnO nanorods had no secondary phase and peaks shifted to the larger angles 2θ due to the increment of the crystal lattice volume.

UV-vis spectra showed that the addition of a single dopant Al or Mg tended to higher the optical transparency at the visible range, while the addition of dopants Al in Al-Mg double doped ZnO nanorods tended to lower the optical tranparency. Changes in band gap energy due to the addition of dopants Al and/or Mg had no clear pattern yet. While the photoluminescence (PL) test results indicated all the ZnO nanorods contained many native crystal lattice defects."

"The electronic and optical properties of a-Al2O3 after induced by 3-keV Ar+ sputtering have been studied quantitatively by use of reflection electron energy loss spectroscopy (REELS) spectra. The band gap values of a-Al2O3 was determined from the onset values of the energy loss spectrum to the background level of REELS spectra as a function of time Ar+ bombardment. The bandgap changes from 8.4 eV before sputtering to 6.2 eV after 4 minutes of sputtering.The optical properties of α-Al2O3 thin films have been determined by comparing the experimental cross section obtained from reflection electron energy loss spectroscopy with the theoretical inelastic scattering cross section, deduced from the simulated energy loss function (ELF) by using QUEELS-ε(k)-REELS software. The peak assignments are based on ELF and compared with reported data on the electronic structure of α-Al2O3 obtained using different techniques. The results demonstrate that the electronic and optical properties before and after surface reduction will provide further understanding in the fundamental properties of α-Al2O3 which will be useful in the design, modeling and analysis of devices applications performance."

"Kombinasi komunikasi yang menggabungkan suara, gambar dari data akhir-akhir ini berkembang dengan sangat pesat terutama perkembangan Internet. Kecepatan informasi merupakan hal terpenting karena kebutuhan mendapatkan informasi sebanyak-banyaknya. Solusinya menggunakan sistem telekomunkasi optik. Beberapa metode telah dikemukakan, namun perkembangannya terus berlanjut. Salah satu komponen yang paling berperan dalam sistem ini adalah EDFA (Erbium Doped Fiber Amplifier).Tulisan ini menganalisa struktur EDFA yang dapat digunakan pada jaringan metro (short distance telecomurncation). Analisa yang digunakan adalah analisa hubungan antara karakteristic gain terhadap daya pompa (pump power), daya input, panjang serat serta filter optik pada serat optik EDFA mode tunggal. Dan hasil analisa numerik dengan simulasi komputer terhadap besaran fisis yang dikandung dalam komponen aktif erbium doped diperoleh bahwa gain serat optik EDFA mode tunggal sangat bergantung pada daya pompa, daya input serta panjang serat. Kesulitan yang timbul adalah bahwa keluaran daya ASE (Amplified Spontaneous Emission) yang tidak sama pada panjang gelombang 1531 nm. Permasalahan tersebut dapat dipecahkan dengan menggunakan komponen pasif filter optik."