scholarly journals Optimization of Different Temperature Annealed Nanostructured CdSe Thin Film for Photodetector Applications

2021 ◽  
Author(s):  
Alagarasan Devarajan ◽  
S. Varadharajaperumal ◽  
K. Deva Arun Kumar ◽  
R. Naik ◽  
A. Arunkumar ◽  
...  
Keyword(s):  
Band Gap ◽  
Optical Parameters ◽  
Stoichiometric Ratio ◽  
X Ray Diffraction ◽  
Thermal Evaporation Method ◽  
X Ray ◽  
Cdse Thin Film ◽  
Highly Sensitive ◽  
Average Grain Size ◽  
Different Temperatures

Abstract In this report, we have discussed the performance of highly sensitive CdSe based photodetector. The CdSe thin films were prepared by thermal evaporation method on the cleaned glass substrate at room temperature. The influence of post annealing on the optical, morphological, structural and photo-electrical properties at different temperatures were investigated. The formation of polycrystalline CdSe films was confirmed from X-ray diffraction (XRD) and Raman studies. The change in surface morphology along with the average grain size of films were observed by field emission scanning electron microscopy (FESEM). The stoichiometric ratio of Cd and Se elements in the deposited films was verified from Energy dispersive X-ray spectroscopy (EDS). The change in various optical parameters like absorption coefficient (α), extinction coefficient (k), optical band gap (Eg), refractive index (n) etc. of the studied films were calculated from the UV-Visible measurement. Importantly, the band gap values were decreased and increased with different annealing temperatures. The CdSe film annealed at 300 °C showed good photo-response and the corresponding optical properties which make them suitable for photodetector applications.

scholarly journals Effect of Re and Tm-site on morphology structure and optical band gap of ReTmO3 (Re: La, Ce, Nd, Gd, Dy, Y and Tm: Fe, Cr) prepared by sol-gel method

2018 ◽  
Vol 64 (4) ◽  
pp. 381
Author(s):  
Muhammad Tufiq Jamil ◽  
Javed Ahmad ◽  
Syed Hamad Bukhari ◽  
Murtaza Saleem
Keyword(s):  
Band Gap ◽  
Sol Gel ◽  
Xrd Analysis ◽  
Sem Analysis ◽  
X Ray Diffraction ◽  
Orthorhombic Crystal ◽  
X Ray ◽  
Average Grain Size ◽  
Auto Combustion ◽  
Uv Visible

Rare earth nano sized pollycrystalline orthoferrites and orthocromites ReT mO3 (Re = La, Nd, Gd, Dy, Y and T m = Fe, Cr) have been synthesized by sol-gel auto combustion citrate method. The samples have been characterized by means of X-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDX), and UV-visible spectroscopy. The samples are single phase as confirmed by XRD analysis and correspond to the orthorhombic crystal symmetry with space group pbnm. Debye Scherer formula and Williamson Hall analysis have been used to calculate the average grain size which is consistent with that of determined from SEM analysis and varied between 25-75 nm. The elemental compositions of all samples have been checked by EDX analysis. Different crystallographic parameters are calculated with strong structural correlation among Re and Tm sites. The optical energy band gap has been calculated by using Tauc relation estimated to be in the range of 1.77 - 1.87 eV and 2.77 - 3.14 eV, for ReFeO3 and ReCrO3, respectively.

scholarly journals Compositional Dependence of Structural Properties of Prepared Alloys and Films

2011 ◽  
Vol 2011 ◽  
pp. 1-6
Author(s):  
M. F. A. Alias ◽  
A. A. J. Al-Douri ◽  
E. M. N. Al-Fawadi ◽  
A. A. Alnajjar
Keyword(s):  
Room Temperature ◽  
Thermal Evaporation ◽  
High Accuracy ◽  
Compositional Dependence ◽  
X Ray Diffraction ◽  
Thermal Evaporation Method ◽  
X Ray ◽  
Glass Substrates ◽  
Different Temperatures ◽  
Good Agreement

Results of a study of alloys and films with various Pb content have been reported and discussed. Films of of thickness 1.5 μm have been deposited on glass substrates by flash thermal evaporation method at room temperature, under vacuum at constant deposition rate. These films were annealed under vacuum around 10−6Torr at different temperatures up to 523 K. The composition of the elements in alloys was determined by standard surfaces techniques such as atomic absorption spectroscopy (AAS) and X-ray fluorescence (XRF), and the results were found of high accuracy and in very good agreement with the theoretical values. The structure for alloys and films is determined by using X-ray diffraction. This measurement reveals that the structure is polycrystalline with cubic structure and there are strong peaks at the direction (200) and (111). The effect of heat treatment on the crystalline orientation, relative intensity, and grain size of films is presented.

Effect of Solution Treatment Temperature on the Microstructure of Fe-33Ni-19Cr Alloy

2020 ◽  
Vol 1010 ◽  
pp. 21-27
Author(s):  
Noraziana Parimin ◽  
Esah Hamzah
Keyword(s):  
Grain Size ◽  
Solution Treatment ◽  
Optical Microscope ◽  
Treatment Temperature ◽  
Solution Treatment Temperature ◽  
X Ray Diffraction ◽  
X Ray ◽  
Solution Treated ◽  
Average Grain Size ◽  
Different Temperatures

The effect of solution treatment temperature on the microstructure, phase present and hardness on Fe-33Ni-19Cr alloy was study in this work. The Fe-33Ni-19Cr alloy was experienced a solution treatment process at six different temperatures which are 950 °C, 1000 °C, 1050 °C, 1100 °C, 1150 °C and 1200 °C for 3 hours soaking time followed by water quench. The average grain size was measured by using linear intercept methods ASTM E112. Microstructure of solution-treated Fe-33Ni-19Cr alloy was characterized by using optical microscope and scanning electron microscope (SEM) equipped with energy dispersive x-ray (EDX) spectrometer. The phase present was analyzed using x-ray diffraction (XRD) technique. The Vickers hardness was used to measure the hardness of solution-treated Fe-33Ni-19Cr alloy. Increasing the solution treatment temperatures were increase the average grain size of solution-treated Fe-33Ni-19Cr alloy. In addition, all samples exhibited an equiaxed matrix grain with slight distribution of precipitates particles. The hardness of solution-treated Fe-33Ni-19Cr alloy was decrease as the solution treatment temperature increase.

scholarly journals Nanosized LaCo0.6Fe0.4O3 perovskites synthesized by citrate sol gel auto combustion method

2014 ◽  
Vol 8 (2) ◽  
pp. 87-92 ◽  
Author(s):  
Unikoth Megha ◽  
Karakat Shijina ◽  
George Varghese
Keyword(s):  
Sol Gel ◽  
Combustion Method ◽  
X Ray Diffraction ◽  
X Ray ◽  
Dense Microstructure ◽  
Metal Nitrates ◽  
Average Grain Size ◽  
Auto Combustion ◽  
Different Temperatures ◽  
Lcr Meter

LaCo0.6Fe0.4O3 (LCFO) nanopowder was synthesized from constituent metal nitrates, citric acid and ethylene glycol by citrate sol gel autocombustion method and calcined at different temperatures. The powders were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDAX) and Fourier transform infrared spectra (FTIR), whereas dielectric properties were investigated with LCR-meter. The FTIR spectra, taken for the xerogel and the sample calcined at 1000?C, confirm that the organic groups were removed during calcination and oxide structure was formed. The XRD result shows that LCFO has rhombhohedral crystal structure with R-3C space group and forms single phase after calcination at 600?C. The activation energy of crystallite growth, determined from the Arrhenius plot, was 17?2 kJ/mol. Surface feature studies of the powders were obtained from SEM. At 1000?C, dense microstructure with wellshaped grain boundaries was obtained and the average grain size was around 400 nm. EDAX confirms the elemental composition. Finally, from the dielectric studies, it was found that the dielectric constant (?r) as well as dielectric loss tangent (tan ?) decreases with increase in frequency.

Thin CuInSi Film Deposited by Magnetron Co-Sputtering

2012 ◽  
Vol 433-440 ◽  
pp. 302-305
Author(s):  
Jian Sheng Xie ◽  
Jin Hua Li ◽  
Ping Luan
Keyword(s):  
Thin Film ◽  
Solar Cells ◽  
Optical Absorption ◽  
Automatic Control ◽  
Band Gap ◽  
Film Surface ◽  
X Ray Diffraction ◽  
X Ray ◽  
Absorption Studies ◽  
Different Temperatures

Thin CuInSi films have been prepared by magnetron co-sputtering, and followed by annealing in N2 atmosphere at different temperatures. The structures of CuInSi films were detected by X-ray diffraction(XRD); X-ray diffraction studies of the annealed films indicate the presence of CuInSi, In2O3 and other peaks. The morphology of the film surface was studied by SEM. The band gap has been estimated from the optical absorption studies and found to be about 1.40 eV, but changes with purity of CuInSi. CuInSi thin film is a potential absorber layer material applied in solar cells and photoelectric automatic control.

Microstructural studies of boron nitride films deposited by microwave plasma-assisted chemical vapor deposition by using trimethyl borazine precursor

1999 ◽  
Vol 14 (3) ◽  
pp. 829-833 ◽  
Author(s):  
A. Ratna Phani
Keyword(s):  
Boron Nitride ◽  
Microwave Plasma ◽  
Cubic Boron Nitride ◽  
Chemical Vapor ◽  
Interplanar Distance ◽  
Stoichiometric Ratio ◽  
X Ray Diffraction ◽  
X Ray ◽  
Different Temperatures ◽  
Deposited Films

Thin films of cubic boron nitride (c-BN) were synthesized using an organometallic precursor trimethylborazine (TMB) which contains both boron and nitrogen in 1 : 1 stoichiometric ratio. The films were deposited at different temperatures ranging from 300 to 500 °C at a pressure of 2 Torr and at 360 W microwave power, using N2 as carrier gas. The deposited films were characterized by Fourier transform infrared spectroscopy (FTIR), x-ray diffraction (XRD), and scanning electron microscopy (SEM), which reveal the presence of amorphous BN and crystalline c-BN in varying proportions. The x-ray diffraction pattern of the deposited films showed a strongest peak at 2θ = 57.1° where the interplanar distance value, d = 2.06 Å, agreed well with the (111) crystallographic orientation of c-BN phase.

X- ray diffraction and dielectric properties of PbSe thin films

2019 ◽  
Vol 15 (34) ◽  
pp. 1-14
Author(s):  
Bushra A. Hasan
Keyword(s):  
Thin Films ◽  
Thermal Activation ◽  
Thermal Evaporation ◽  
Thermal Activation Energy ◽  
Dielectric Constants ◽  
Conductivity Measurements ◽  
X Ray Diffraction ◽  
Thermal Evaporation Method ◽  
X Ray ◽  
Glass Substrates

Lead selenide PbSe thin films of different thicknesses (300, 500, and 700 nm) were deposited under vacuum using thermal evaporation method on glass substrates. X-ray diffraction measurements showed that increasing of thickness lead to well crystallize the prepared samples, such that the crystallite size increases while the dislocation density decreases with thickness increasing. A.C conductivity, dielectric constants, and loss tangent are studied as function to thickness, frequency (10kHz-10MHz) and temperatures (293K-493K). The conductivity measurements confirm confirmed that hopping is the mechanism responsible for the conduction process. Increasing of thickness decreases the thermal activation energy estimated from Arhinus equation is found to decrease with thickness increasing. The increase of thickness lead to reduce the polarizability α while the increasing of temperature lead to increase α.

Investigation of the products of carbothermal reduction of yttrium oxide by the hydrolysis method

1984 ◽  
Vol 49 (4) ◽  
pp. 936-943 ◽  
Author(s):  
Bohumil Hájek ◽  
Pavel Karen ◽  
Vlastimil Brožek
Keyword(s):  
Yttrium Oxide ◽  
Carbothermal Reduction ◽  
Stoichiometric Ratio ◽  
X Ray Diffraction ◽  
X Ray ◽  
Hydrolysis Method ◽  
Sample Decomposition ◽  
Products Of Reaction ◽  
Hydrolysis Of ◽  
Lower Carbon

For the investigation of the products of reaction of yttrium oxide with carbon mixed in various proportions, the chemical and X-ray diffraction methods of analysis were combined with the gas chromatographic analysis of the mixture of hydrocarbons and hydrogen formed on the sample decomposition with water. The carboreduction of Y2O3 was examined at relatively low temperatures, convenient for obtaining the reaction intermediates in higher yields. At 1 600 °C and pressures of 10-3 Pa the reduction of a mixture of Y2O3 with carbon in a stoichiometric ratio of 1 : 7 yields YC2 in equilibrium with 20% of Y2OC phase. At lower carbon contents (down to the Y2O3 : C ratio of 1 : 2) tha fraction of the Y2OC phase increases up to approximately 30%. In addition to Y2O3, the reaction mixture contains also Y2C, Y2OC and a phase giving propyne on hydrolysis. The presence of traces of C3 hydrocarbons and small amounts of methane in the product of hydrolysis of the carbide sample prepared by the carbothermal reduction of the oxide can be explained in terms of the occurrence of the Y15C19 phase, probably substituted in part by oxygen, and of the Y2OC phase. The results are compared with those obtained previously for the Sc2O3 + C system.

Effect of Temperature on Fe3O4 Magnetic Nanoparticles Prepared by Coprecipitation Method

2014 ◽  
Vol 900 ◽  
pp. 172-176 ◽  
Author(s):  
Ji Mei Niu ◽  
Zhi Gang Zheng
Keyword(s):  
Magnetic Nanoparticles ◽  
Coprecipitation Method ◽  
Effect Of Temperature ◽  
Vibrating Sample Magnetometer ◽  
X Ray Diffraction ◽  
X Ray ◽  
Magnetic Carriers ◽  
Average Grain Size ◽  
Or Gene ◽  
Block Temperature

The Fe3O4 magnetic nanoparticles obtained by the aqueous coprecipitation method are characterized systematically using scanning electron microscope, X-ray diffraction and vibrating sample magnetometer. These magnetic nanoparticles are spheric, dispersive, and have average grain size of 50 nm. The size and magnetic properties of Fe3O4 nanoparticles can be tuned by the reaction temperature. All samples exhibit high saturation magnetization (Ms=53.4 emu·g-1) and superparamagnetic behavior with a block temperature (TB) of 215K. These properties make such Fe3O4 magnetic nanoparticles worthy candidates for the magnetic carriers of targeted-drug or gene therapy in future.

scholarly journals A Superhydrophobic, Antibacterial, and Durable Surface of Poplar Wood

Nanomaterials ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1885
Author(s):  
Xinyu Wu ◽  
Feng Yang ◽  
Jian Gan ◽  
Zhangqian Kong ◽  
Yan Wu
Keyword(s):  
Stearic Acid ◽  
Antibacterial Properties ◽  
Alkali Resistance ◽  
Poplar Wood ◽  
X Ray Diffraction ◽  
X Ray ◽  
Different Temperatures ◽  
Acid And Alkali Resistance ◽  
The Stability

The silver particles were grown in situ on the surface of wood by the silver mirror method and modified with stearic acid to acquire a surface with superhydrophobic and antibacterial properties. Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and X-ray energy spectroscopy (XPS) were used to analyze the reaction mechanism of the modification process. Scanning electron microscopy (SEM) and contact angle tests were used to characterize the wettability and surface morphology. A coating with a micro rough structure was successfully constructed by the modification of stearic acid, which imparted superhydrophobicity and antibacterial activity to poplar wood. The stability tests were performed to discuss the stability of its hydrophobic performance. The results showed that it has good mechanical properties, acid and alkali resistance, and UV stability. The durability tests demonstrated that the coating has the function of water resistance and fouling resistance and can maintain the stability of its hydrophobic properties under different temperatures of heat treatment.

Sign in / Sign up

Export Citation Format

Share Document