scholarly journals Optical, structural and electrical properties of nanosized zinc oxide sintered films for photovoltaic applications

2013 ◽  
Vol 45 (1) ◽  
pp. 13-19 ◽  
Author(s):  
V. Kumar ◽  
D.K. Dwivedi ◽  
P. Agrawal

Zinc oxide films have been deposited on ultra-clean glass substrates by screenprinting method followed by sintering process. Optimum conditions for preparing good quality screen-printed films have been found. The optical band gap of the films has been studied using reflection spectra in wavelength range 325-600 nm by using double beam spectrophotometer. X-ray diffraction studies revealed that the films are polycrystalline in nature, single phase exhibiting wurtzite (hexagonal) structure with strong preferential orientation of grains along the (101) direction. Surface morphology of films has been studied by scanning electron microscopy (SEM) technique. The electrical resistivity of the films was measured in vacuum by two probe technique. PACS: 78.20.Ci; 78.50.Ge; 78.66.-w; 78.66.Hf.

2014 ◽  
Vol 908 ◽  
pp. 124-128 ◽  
Author(s):  
S.B. Chen ◽  
Z.Y. Zhong

Thin films of transparent conducting gallium and titanium doped zinc oxide (GTZO) were prepared on glass substrates by magnetron sputtering technique using a sintered ceramic target. The microstructural properties of the deposited thin films were characterized with X-ray diffraction (XRD). The results demonstrated that the polycrystalline GTZO thin films consist of the hexagonal crystal structures with c-axis as the preferred growth orientation normal to the substrate, and that the working pressure significantly affects the crystal structures of the thin films. The GTZO thin film deposited at the working pressure of 0.4 Pa has the best crystallinity, the largest grain size and the lowest stress.


2018 ◽  
Vol 930 ◽  
pp. 79-84
Author(s):  
Juliana Simões Chagas Licurgo ◽  
Herval Ramos Paes Junior

In this work, copper-doped zinc oxide films (ZnO:Cu) were deposited by spray pyrolysis on glass substrates. The influence of doping concentration (0-10 at.%) on morphological, structural, optical and electrical properties of the ZnO:Cu films was investigated. Electrical characterization consisted in measuring the variation of electrical conductivity with temperature; they presented a typical semiconductor material behavior. Based on x-ray diffraction (XRD) analysis, it was able to confirm that the films are polycrystalline having a wurtzite hexagonal structure, preferentially oriented in the c-axis (002), and the crystallite size ranged from 41.60 to 50.70 nm. The optical characterization revealed that ZnO:Cu films present band gap energy between 3.18 and 3.27 eV. The films were homogeneous with good adhesion to the substrate. The results indicate the viability of using them in optoelectronic devices.


2013 ◽  
Vol 873 ◽  
pp. 426-430
Author(s):  
Xian Wu Xiu ◽  
Li Xu ◽  
Cheng Qiang Zhang

Molybdenum-doped zinc oxide (MZO) films have been prepared by RF magnetron sputtering on glass substrates at room temperature. The structural, electrical and optical properties of the films vary with sputtering power from 15 W to 70 W are investigated. X-ray diffraction (XRD) analysis reveals that all the films are polycrystalline with the hexagonal structure and have a preferred orientation along thecaxis perpendicular to the substrate. The resistivity increases with the increase of the RF power. The lowest resistivity achieved is 5.4×10-3Ω cm at a RF power of 15 W with a Hall mobility of 11 cm2V-1s-1and a carrier concentration of 1.1×1019cm-3. The average transmittance drops from 85% to 81% in the visible range and the optical band gap decreases from 3.26 eV to 3.19 eV with the increase of the RF power.


2007 ◽  
Vol 2007 ◽  
pp. 1-5 ◽  
Author(s):  
V. Kumar ◽  
G. S. Sandhu ◽  
T. P. Sharma ◽  
M. Hussain

The II-VI polycrystalline semiconducting materials have come under increased scrutiny because of their wide use in the cost reduction of devices for photovoltaic applications.Cd1−XZnXTe is one of the II-VI ternary semiconductor materials whose bandgap can be tailored to any value between 1.48–2.26 eV as X varies from 0 to 1. It is promising material for high-efficiency solar cells, switching, and other optoelectronic devices. Polycrystalline thin film ofCd1−XZnXTe with variable composition (0≤X≤1) has been deposited on ultraclean glass substrates by screen printing method followed by sintering process. The optical and structural properties ofCd1−XZnXTe thin films have been examined. The optical bandgap of these films is studied using reflection spectra in wavelength range of 350–900 nm by using double beam spectrophotometer. The structure of sample was determined from X-ray diffraction patterns. The films were polycrystalline in nature having wurtzite (Hexagonal) structure over the whole range studied. The lattice parameters vary almost linearly with the composition parameterX, following Vegard's law. Sintering is a very simple and viable method compared to other cost-intensive methods. The results of the present investigation will be useful in characterizing the material CdZnTe for its applications in photovoltaics.


2014 ◽  
Vol 11 (3) ◽  
pp. 1257-1260
Author(s):  
Baghdad Science Journal

In this work the effect of annealing temperature on the structure and the electrical properties of Bi thin films was studied, the Bi films were deposited on glass substrates at room temperature by thermal evaporation technique with thickness (0.4 µm) and rate of deposition equal to 6.66Å/sec, all samples are annealed in a vacuum for one hour. The X-ray diffraction analysis shows that the prepared samples are polycrystalline and it exhibits hexagonal structure. The electrical properties of these films were studied with different annealing temperatures, the d.c conductivity for films decreases from 16.42 ? 10-2 at 343K to 10.11?10-2 (?.cm)-1 at 363K. The electrical activation energies Ea1 and Ea2 increase from 0.031 to 0.049eV and from 0.096 to 0. 162 eV with increasing of annealing temperature from 343K to 363K, respectively. Hall measurements showed that all the films are p-type.


Author(s):  
T. A. Emma ◽  
M. P. Singh

Optical quality zinc oxide films have been characterized using reflection electron diffraction (RED), replication electron microscopy (REM), scanning electron microscopy (SEM), and X-ray diffraction (XRD). Significant microstructural differences were observed between rf sputtered films and planar magnetron rf sputtered films. Piezoelectric materials have been attractive for applications to integrated optics since they provide an active medium for signal processing. Among the desirable physical characteristics of sputtered ZnO films used for this and related applications are a highly preferred crystallographic texture and relatively smooth surfaces. It has been found that these characteristics are very sensitive to the type and condition of the substrate and to the several sputtering parameters: target, rf power, gas composition and substrate temperature.


2014 ◽  
Vol 602-603 ◽  
pp. 871-875
Author(s):  
Yen Pei Fu ◽  
Jian Jhih Chen

In this study, ZnO films, prepared by Chemical Bath Deposition (CBD), are applied as the conductive layers for thin film solar cells. Zinc acetate is used as a source of zinc, and different proportions of ammonia solution are added and well mixed. The growth of zinc oxide films in reaction solutions is taken place at 80°C and then heated to 500°C for one hour. In this study, the different ammonia concentrations and deposition times is controlled. The thin film structure is Hexagonal structure, which is determined by X-ray diffraction spectrometer (XRD) analysis. Scanning electron microscopy (SEM) is used as the observation of surface morphology, the bottom of the film is the interface where the heterogeneous nucleation happens. With the increase of deposition time, there were a few attached zinc oxide particles, which is formed by homogeneous nucleation. According to UV / visible light (UV / Vis) absorption spectrometer transmittance measurements and the relationship between/among the incident wavelength, it can be converted to the energy gaps (Eg), which are about 3.0 to 3.2eV, by using fluorescence spectroscopy analysis. The emission of zinc oxide films has two wavelengths which are located on 510nm and 570nm. According to Based on the all analytic results, the ammonia concentration at 0.05M, and the deposition time is 120 minutes, would obtain the conditions of ZnO films which is more suitable for applications of conductive layer material in thin film solar cell.


Polymers ◽  
2021 ◽  
Vol 13 (13) ◽  
pp. 2062
Author(s):  
Yu-Hsun Nien ◽  
Zhi-Xuan Kang ◽  
Tzu-Yu Su ◽  
Chih-Sung Ho ◽  
Jung-Chuan Chou ◽  
...  

Potentiometric biosensors based on flexible arrayed silver paste electrode and copper-doped zinc oxide sensing film modified by iron-platinum nanoparticles (FePt NPs) are designed and manufactured to detect lactate in human. The sensing film is made of copper-doped zinc oxide (CZO) by a radio frequency (RF) sputtering system, and then modified by iron-platinum nanoparticles (FePt NPs). The surface morphology of copper-doped zinc oxide (CZO) is analyzed by scanning electron microscope (SEM). FePt NPs are analyzed by X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). The average sensitivity, response time, and interference effect of the lactate biosensors are analyzed by voltage-time (V-T) measurement system. The electrochemical impedance is analyzed by electrochemical impedance spectroscopy (EIS). The average sensitivity and linearity over the concentration range 0.2 mM–5 mM are 25.32 mV/mM and 0.977 mV/mM, respectively. The response time of the lactate biosensor is 16 s, with excellent selectivity.


2010 ◽  
Vol 7 (1) ◽  
pp. 69-75
Author(s):  
Baghdad Science Journal

Undoped and Co-doped zinc oxide (CZO) thin films have been prepared by spray pyrolysis technique using solution of zinc acetate and cobalt chloride. The effect of Co dopants on structural and optical properties has been investigated. The films were found to exhibit maximum transmittance (~90%) and low absorbance. The structural properties of the deposited films were examined by x-ray diffraction (XRD). These films, deposited on glass substrates at (400? C), have a polycrystalline texture with a wurtzite hexagonal structure, and the grain size was decreased with increasing Co concentration, and no change was observed in lattice constants while the optical band gap decreased from (3.18-3.02) eV for direct allowed transition. Other parameters such as Texture Coefficient (Tc), dislocation density (?) and number of crystals (M) were also calculated .


2014 ◽  
Vol 552 ◽  
pp. 56-61 ◽  
Author(s):  
Tsuyoshi Ogino ◽  
Jesse R. Williams ◽  
Ken Watanabe ◽  
Isao Sakaguchi ◽  
Shunichi Hishita ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document