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Full-Text Articles in Physics
Production Of Zno Thin Films Used In Solar Cell With A Sol-Gel Homemade Dip Coater Technique And Investigated Of Their Structural, Morphological And Optical Properties, Z. Gã¼Ltekin, C. Akay, N. A. Gã¼Ltekin, M. Alper
Production Of Zno Thin Films Used In Solar Cell With A Sol-Gel Homemade Dip Coater Technique And Investigated Of Their Structural, Morphological And Optical Properties, Z. Gã¼Ltekin, C. Akay, N. A. Gã¼Ltekin, M. Alper
Eurasian Journal of Physics and Functional Materials
We designed a homemade dip coater controlled by an Arduino microcontroller to produce semiconductor metal oxide films such as ZnO, CoO, and NiO. The developed device was successfully used to deposit ZnO film on a glass substrate. The structural, surface, and optical properties of the film were investigated. XRD patterns showed that the film is predominantly a hexagonal wurtzite crystalline structure. Scanning electron microscopy (SEM) images showed that the ZnO film was uniformly and homogeneously coated on the glass substrate. EDX analysis confirmed the presence of Zn and O in the film structure. Optical characterization by UV-visible spectrometry showed that …
Electron Hole Capture Centers In An Irradiated K2so4-Cu Crystal, T. N. Nurakhmetov, Zh. M. Salikhodzha, R. Z. Bakhtizin, A. M. Zhunusbekov, A. Zh. Kainarbay, D. H. Daurenbekov, B. M. Sadykova, K. B. Zhangylyssov, B. N. Yussupbekova
Electron Hole Capture Centers In An Irradiated K2so4-Cu Crystal, T. N. Nurakhmetov, Zh. M. Salikhodzha, R. Z. Bakhtizin, A. M. Zhunusbekov, A. Zh. Kainarbay, D. H. Daurenbekov, B. M. Sadykova, K. B. Zhangylyssov, B. N. Yussupbekova
Eurasian Journal of Physics and Functional Materials
The methods of vacuum ultraviolet and thermal activation spectroscopy were used to measure the excitation spectra of impurity radiation in the fundamental absorption band of K2SO4-Cu crystals at 15 K and 300 K. An energy transfer was detected from the base to Cu+ impurities. The band gap of crystals K2SO4 was estimated. In K2SO4-Cu crystals, recombination radiation bands were detected at 2.95 ÷ 3.0 eV corresponding to electron hole capture centers.
Structural, Optical And Electrical Properties Of Yttrium-Doped Hafnium Oxide Nanocrystalline Thin Films, Abhilash Kongu
Structural, Optical And Electrical Properties Of Yttrium-Doped Hafnium Oxide Nanocrystalline Thin Films, Abhilash Kongu
Open Access Theses & Dissertations
Hafnium oxide (HfO2) has emerged as the most promising high-k dielectric for Metal-Oxide-Semiconductor (MOS) devices and has been highlighted as the most suitable dielectric materials to replace silicon oxide because of its comprehensive performance. In the present research, yttrium-doped HfO2 (YDH) thin films were fabricated using RF magnetron sputter deposition onto Si (100) and quartz with a variable thickness. Cross-sectional scanning electron microscopy coupled with Filmetrics revealed that film thickness values range from 700 A° to 7500 A°. Electrical properties such as AC Resistivity and current-voltage (I-V) characteristics of YDH films were studied. YDH films that were relatively thin (<1500 A°) crystallized in monoclinic phase while thicker films crystallized in cubic phase. The band gap (Eg) of the films was calculated from the optical measurements. The band gap was found to be ∼5.60 eV for monoclinic while it is ∼6.05 eV for cubic phase of YDH films. Frequency dependence of the electrical resistivity (ρac) and the total conductivity of the films were measured. Resistivity decreased (by three orders of magnitude) with increasing frequency from 100 Hz to 1 MHz, attributed due to the hopping mechanism in YDH films. Whereas, while ρac∼1Ω-m at low frequencies (100 Hz), it decreased to ∼ 104 Ω-cm at higher frequencies (1 MHz). Aluminum (Al) metal electrodes were deposited to fabricate a thin film capacitor with YDH layer as dielectric film thereby employing Al-YDH-Si capacitor structure. The results indicate that the capacitance of the films decrease with increasing film thickness. A detailed analysis of the electrical characteristics of YDH films is presented.
Effect Of Ga Content On Defect States In Cuin1-XGaXSe2 Photovoltaic Devices, Jennifer T. Heath, J. David Cohen, William N. Shafarman, Dongxiang Liao, Angus Rockett
Effect Of Ga Content On Defect States In Cuin1-XGaXSe2 Photovoltaic Devices, Jennifer T. Heath, J. David Cohen, William N. Shafarman, Dongxiang Liao, Angus Rockett
Faculty Publications
Defects in the band gap of CuIn1-xGaxSe2 have been characterized using transient photocapacitance spectroscopy. The measured spectra clearly show response from a band of defects centered around 0.8 eV from the valence band edge as well as an exponential distribution of band tail states. Despite Ga contents ranging from Ga/(In+Ga)=0.0 to 0.8, the defect bandwidth and its position relative to the valence band remain constant. This defect band may act as an important recombination center, contributing to the decrease in device efficiency with increasing Ga content.