Optical Characterization of Al-doped ZnO Films via Sol-gel Method Using Spectroscopic Ellipsometry

Background: Al-doped ZnO thin films are considered as a promising alternative to ITO in optoelectronic applications. In this work, Al-doped ZnO thin films were prepared using sol-gel spin coating technique. Experimental: The optical properties of the films such as refractive index, extinction coefficient, dielectric function and the absorption coefficient were examined using spectroscopic ellipsometry method in the wavelength range of 300 to 900 nm. The effect of Al doping on ZnO thin films with different Al concentrations was significant. Tauc relation was used to estimate the optical band gap energy of the films. Results: The calculated values of band gap energy were obtained between 3.10 to 3.25 eV. Also the fraction of voids was calculated using Aspnes theory. Conclusion: The free carrier concentration value was obtained in the order of 1019 cm-3.

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Optical and Electronic Analysis of Pure and Fe-Doped ZnO Thin Films Using Spectroscopic Ellipsometry and Kramers–Kronig Method

International Journal of Nanoscience ◽

10.1142/s0219581x18500138 ◽

2019 ◽

Vol 18 (01) ◽

pp. 1850013 ◽

Cited By ~ 1

Author(s):

Maryam Motallebi Aghgonbad ◽

Hassan Sedghi

Keyword(s):

Thin Films ◽

Band Gap ◽

Spectroscopic Ellipsometry ◽

Optical Band Gap ◽

Band Gap Energy ◽

Zno Thin Films ◽

Fe Doping ◽

Gap Energy ◽

Optical And Electronic Properties ◽

Doped Zno

In the present work, pure and Fe-doped ZnO thin films were deposited on glass substrates by sol–gel method. Zinc acetate and iron nitrate were used as the starting material and dopant source, respectively. The concentration of Fe doping was 6[Formula: see text]at.% and 8[Formula: see text]at.%. The optical and electronic properties of pure and Fe-doped ZnO thin films such as refraction index, extinction coefficient, dielectric function and optical band gap energy of the layers were obtained by spectroscopic ellipsometry method in the wavelength range of 300–900[Formula: see text]nm. The incidence angle of the layers kept 70[Formula: see text]. Also data obtained by Kramers–Kronig relations were used for comparison. The influence of Fe-doping concentration on the optical and electronic properties of thin films was studied. The transmittance data of ZnO thin films showed that 6[Formula: see text]at.% Fe-doped ZnO thin film has the highest transmittance value. Dielectric function of pure ZnO films was found to be higher compared with Fe-doped ones. Also it can be deduced from the results that Fe doping influences the optical band gap energy of thin films.

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Band gap energy of pure and Al-doped ZnO thin films

Journal of the European Ceramic Society ◽

10.1016/s0955-2219(03)00490-4 ◽

2004 ◽

Vol 24 (6) ◽

pp. 1869-1872 ◽

Cited By ~ 185

Author(s):

F.K. Shan ◽

Y.S. Yu

Keyword(s):

Thin Films ◽

Band Gap ◽

Band Gap Energy ◽

Zno Thin Films ◽

Gap Energy ◽

Doped Zno

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The calculation of the optical gap energy of ZnXO (X = Bi, Sn and Fe)

Open Physics ◽

10.1515/phys-2016-0080 ◽

2016 ◽

Vol 14 (1) ◽

pp. 714-720 ◽

Cited By ~ 2

Author(s):

Said Benramache ◽

Boubaker Benhaoua

Keyword(s):

Thin Films ◽

Optical Properties ◽

Spray Deposition ◽

Band Gap Energy ◽

Zno Thin Films ◽

Zno Films ◽

Gap Energy ◽

Optical Gap ◽

Optical Gap Energy ◽

Doped Zno

AbstractIn this paper, a new mathematical model has been developed to calculate the optical properties of nano materials a function of their size and structure. ZnO has good characterizatics in optical, electrical, and structural crystallisation; We will demonstrate that the direct optical gap energy of ZnO films grown by US and SP spray deposition can be calculated by investigating the correlation between solution molarity, doping levels of doped films and their Urbache energy. A simulation model has been developed to calculate the optical band gap energy of undoped and Bi, Sn and Fe doped ZnO thin films. The measurements by thus proposed models are in agreement with experimental data, with high correlation coefficients in the range 0.94-0.99. The maximum calculated enhancement of the optical gap energy of Sn doped ZnO thin films is always higher than the enhancement attainable with an Fe doped film, where the minimum error was found for Bi and Sn doped ZnO thin films to be 2,345 and 3,072%, respectively. The decrease in the relative errors from undoped to doped films can be explained by the good optical properties which can be observed in the fewer number of defects as well as less disorder.

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A Study on Effect of Sol Aging Time on Optical Properties of ZnO Thin Films: Spectroscopic Ellipsometry Method

Micro and Nanosystems ◽

10.2174/1876402911666190313155304 ◽

2019 ◽

Vol 11 (2) ◽

pp. 100-108 ◽

Cited By ~ 1

Author(s):

Ehsan Motallebi Aghkonbad ◽

Maryam Motallebi Aghgonbad ◽

Hassan Sedghi

Keyword(s):

Thin Films ◽

Optical Properties ◽

Band Gap ◽

Aging Time ◽

Imaginary Part ◽

Spectroscopic Ellipsometry ◽

Annealing Temperature ◽

Band Gap Energy ◽

Zno Thin Films ◽

Gap Energy

Background: Due to wide band gap and large excitonic binding energy, being inexpensive, abundance in nature and easy synthesis ZnO is a promising candidate in many applications such as solar cells. Experimental: In the current work a series of ZnO thin films were deposited on glass substrates using sol-gel method to investigate the change in optical behavior of the film with sol aging time (asprepared, 8, 16, 24 and 32 hours) and the annealing temperature (300ᵒC and 500ᵒC). The optical properties of thin films were explored using spectroscopic ellipsometry method including the real and imaginary part of refractive index, real and imaginary part of dielectric function and band gap energy of the layers in the 300-900 nanometer wavelength range. Results: It can be deduced from the results that sol aging time and annealing temperature, affect the optical properties of the samples. Using single oscillator energy model of Wemple and Di Domenico parameters such as free charge carrier concentration ratio to effective mass, and plasma frequency, were calculated. Conclusion: The films prepared using 24 h aged solution, had the highest transmittance and the largest band gap energy.

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Development of flexible Mg and Ga co-doped ZnO thin films with wide band gap energy and transparent conductive characteristics

Journal of Alloys and Compounds ◽

10.1016/j.jallcom.2013.09.133 ◽

2014 ◽

Vol 585 ◽

pp. 608-613 ◽

Cited By ~ 13

Author(s):

Seung Wook Shin ◽

In Young Kim ◽

G.V. Kishor ◽

Yeong Yung Yoo ◽

Young Baek Kim ◽

...

Keyword(s):

Thin Films ◽

Band Gap ◽

Wide Band ◽

Band Gap Energy ◽

Zno Thin Films ◽

Wide Band Gap ◽

Gap Energy ◽

Doped Zno ◽

Co Doped

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Photocatalytic Properties of ZnO and Ag Doped ZnO Thin Films

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.685.3 ◽

2014 ◽

Vol 685 ◽

pp. 3-6

Author(s):

Ying Lian Wang ◽

Jun Yao Ye

Keyword(s):

Thin Films ◽

Annealing Temperature ◽

Sol Gel ◽

Structural Features ◽

Photocatalytic Properties ◽

Zno Thin Films ◽

Molar Ratio ◽

Zno Films ◽

Doped Zno ◽

Excellent Adhesion

Pure ZnO thin films and Ag doped ZnO thin films were prepared on quartz substrates by sol-gel process. Structural features and UV absorption spectrum have been studied by XRD and UV-Vis-Nir scanning spectrophotometer. Taking phenol as pollutants, further study of the effect of different annealing temperature and Ag dopant amount of ZnO films on photocatalytic properties was carried out. The results showed that, the optimal annealing temperature on photocatalytic degradation of phenol in this experiment was 300 °C, the best molar ratio of ZnO and Ag was 30:1, which was better than pure ZnO film greatly. Excellent adhesion, recyclable and efficient degradation Ag doped ZnO thin films were found in this experiment.

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Spectroscopic ellipsometry studies of sol-gel-derived Cu-doped ZnO thin films

Thin Solid Films ◽

10.1016/j.tsf.2014.02.097 ◽

2014 ◽

Vol 571 ◽

pp. 605-608 ◽

Cited By ~ 7

Author(s):

Shenghong Yang ◽

Yueli Zhang ◽

Dang Mo

Keyword(s):

Thin Films ◽

Spectroscopic Ellipsometry ◽

Sol Gel ◽

Zno Thin Films ◽

Doped Zno

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Influence of thickness on the optical properties of Sb doped ZnO thin films

Journal of Bangladesh Academy of Sciences ◽

10.3329/jbas.v38i1.20217 ◽

2014 ◽

Vol 38 (1) ◽

pp. 93-96

Author(s):

E Hoq ◽

MRA Bhuiyan ◽

J Begum

Keyword(s):

Thin Films ◽

Optical Properties ◽

Band Gap ◽

Zno Thin Films ◽

Zno Films ◽

Thermal Evaporation Method ◽

Doped Zno ◽

High Absorption Coefficient ◽

Academy Of Sciences ◽

High Absorption

Sb doped ZnO thin films having various thicknesses have been prepared onto glass substrate by using thermal evaporation method. The atomic compositions of the grown films have been determined by Energy Dispersive Analysis of X-ray (EDAX) method. The optical properties were measured by using a UV-VIS-NIR spectrophotometer (300 to 2500 nm). The EDAX analysis revealed that Sb is doped into the ZnO films. Optical properties showed high absorption coefficient (~105/cm) that direct allowed transition band gap. The optical band gap of the ZnO thin films became reduced due to the doping of Sb. DOI: http://dx.doi.org/10.3329/jbas.v38i1.20217 Journal of Bangladesh Academy of Sciences, Vol. 38, No. 1, 93-96, 2014

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Effect of Ruthenium Concentration on Structural and I-V Characteristics of ZnO Thin Films by Sol–Gel Method

Journal of Molecular and Engineering Materials ◽

10.1142/s2251237317500046 ◽

2017 ◽

Vol 05 (01) ◽

pp. 1750004

Author(s):

R. Vettumperumal ◽

S. Kalyanaraman ◽

R. Thangavel

Keyword(s):

Thin Films ◽

Sol Gel ◽

Zno Thin Films ◽

Zno Films ◽

X Ray Diffraction ◽

Axis Orientation ◽

Gel Method ◽

X Ray ◽

Sol Gel Method ◽

Doped Zno

Nanocrystalline ruthenium (Ru)-doped ZnO thin films on sapphire substrate was prepared using sol–gel method by spin coating technique. The structural and I-V characteristics of Ru doped ZnO thin films were studied from the X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM) analysis and Raman spectroscopy. X-ray diffraction (XRD) results revealed that the deposited films belonged to hexagonal wurtzite structure with c-axis orientation. It is also confirmed from the Raman spectra. Enhancement of longitudinal optical (LO) phonon is observed by the strong electron–phonon interaction. An observed increment in sheet resistance with increase in dopant percentage of Ru (1–2[Formula: see text]mol%) in ZnO films was found and better I-V characteristic behavior was observed at 1[Formula: see text]mol% of Ru-doped ZnO thin films. Trap limited current flow inside the material was calculated from the log I versus log V plot in the higher voltage region.

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