scholarly journals Correlation between damage evolution, structural and optical properties of Xe implanted CrN thin films

2018 ◽  
Vol 12 (3) ◽  
pp. 199-208
Author(s):  
Maja Popovic ◽  
Mirjana Novakovic ◽  
Kun Zhang ◽  
Miodrag Mitric ◽  
Natasa Bibic ◽  
...  

Polycrystalline CrN thin films were irradiated with Xe ions. The irradiation-induced modifications on structural and optical properties of the films were investigated. The CrN films were deposited on Si(100) wafers with the thickness of 280 nm, by using DC reactive sputtering. After deposition, the films were implanted at room temperature with 400 keV Xe ions with the fluences of 5-20?1015 ions/cm2. The films were then annealed at 700 ?C in vacuum for 2 h. The combination of Rutherford backscattering spectrometry (RBS), X-ray diffraction (XRD) and transmission electron microscopy (TEM) was used for structural analyses, while changes in optical properties were monitored by spectroscopic ellipsometry. We also measured the electrical resistivity of the samples using a four point probe method. RBS analysis reveals that the concentration of Xe in the layers increases with ion fluence reaching the value of around 1.5 at.% for the highest ion dose, at a depth of 73 nm. XRD patterns show that the irradiation results in the decrease of the lattice constant in the range of 0.4160-0.4124 nm. Irradiation also results in the splitting of 200 line indicating the tetragonal distortion of CrN lattice. TEM studies demonstrate that after irradiation the columnar microstructure is partially destroyed within _90 nm, introducing a large amount of damage in the CrN layers. Spectroscopic ellipsometry analysis shows that the optical band gap of CrN progressively reduces from 3.47 eV to 2.51 eV with the rise in ion fluence up to 20?1015 ions/cm2. Four point probe measurements of the films indicated that as the Xe ion fluence increases, the electrical resistivity rises from 770 to 1607 ?Wcm. After post-implantation annealing crystalline grains become larger and lattice distortion disappears, which influences optical band gap values and electrical resistivity of CrN.

2015 ◽  
Vol 1109 ◽  
pp. 544-548 ◽  
Author(s):  
Jian Bo Liang ◽  
Xu Yang Li ◽  
Naoki Kishi ◽  
Tetsuo Soga

Single phase CuO films have been successfully synthesized by thermal oxidation of cupper foil in air with water vapor. The structural and optical properties of CuO films were investigated. It is observed that the grain size increases with increasing the oxidation temperature. The optical band gap of CuO film is determined by the transmittance and reflectance spectra.


Crystals ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 132 ◽  
Author(s):  
Theopolina Amakali ◽  
Likius. S. Daniel ◽  
Veikko Uahengo ◽  
Nelson Y. Dzade ◽  
Nora H. de Leeuw

Zinc oxide (ZnO) is a versatile and inexpensive semiconductor with a wide direct band gap that has applicability in several scientific and technological fields. In this work, we report the synthesis of ZnO thin films via two simple and low-cost synthesis routes, i.e., the molecular precursor method (MPM) and the sol–gel method, which were deposited successfully on microscope glass substrates. The films were characterized for their structural and optical properties. X-ray diffraction (XRD) characterization showed that the ZnO films were highly c-axis (0 0 2) oriented, which is of interest for piezoelectric applications. The surface roughness derived from atomic force microscopy (AFM) analysis indicates that films prepared via MPM were relatively rough with an average roughness (Ra) of 2.73 nm compared to those prepared via the sol–gel method (Ra = 1.55 nm). Thin films prepared via MPM were more transparent than those prepared via the sol–gel method. The optical band gap of ZnO thin films obtained via the sol–gel method was 3.25 eV, which falls within the range found by other authors. However, there was a broadening of the optical band gap (3.75 eV) in thin films derived from MPM.


2010 ◽  
Vol 654-656 ◽  
pp. 1764-1767 ◽  
Author(s):  
Kateryna Bazaka ◽  
Mohan V. Jacob

This study presents the effect of iodine doping on optical and surface properties of polyterpenol thin films deposited from non-synthetic precursor by means of plasma polymerisation. Spectroscopic ellipsometry studies showed iodine doping reduced the optical band gap from 2.82 eV to 1.50 eV for pristine and doped samples respectively. Higher levels of doping notably reduced the transparency of films, an issue if material is considered for applications that require high transparency. Contact angle studies demonstrated higher hydrophilicity for films deposited at increased doping levels, results confirmed by XPS Spectroscopy and FTIR. Doping had no significant effect on the surface profile or roughness of the film.


Coatings ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 1064
Author(s):  
Iosif-Daniel Simandan ◽  
Florinel Sava ◽  
Angel-Theodor Buruiana ◽  
Ion Burducea ◽  
Nicu Becherescu ◽  
...  

ZnS is a wide band gap material which was proposed as a possible candidate to replace CdS as a buffer layer in solar cells. However, the structural and optical properties are influenced by the deposition method. ZnS thin films were prepared using magnetron sputtering (MS), pulsed laser deposition (PLD), and a combined deposition technique that uses the same bulk target for sputtering and PLD at the same time, named MSPLD. The compositional, structural, and optical properties of the as-deposited and annealed films were inferred from Rutherford backscattering spectrometry, X-ray diffraction, X-ray reflectometry, Raman spectroscopy, and spectroscopic ellipsometry. PLD leads to the best stoichiometric transfer from target to substrate, MS makes fully amorphous films, whereas MSPLD facilitates obtaining the densest films. The study reveals that the band gap is only slightly influenced by the deposition method, or by annealing, which is encouraging for photovoltaic applications. However, sulphur vacancies contribute to lowering the bandgap and therefore should be controlled. Moreover, the results add valuable information towards the understanding of ZnS polymorphism. The combined MSPLD method offers several advantages such as an increased deposition rate and the possibility to tune the optical properties of the obtained thin films.


2012 ◽  
Vol 229-231 ◽  
pp. 10-13
Author(s):  
Liang Yan Chen ◽  
Chao Fang

ZnSe thin films were obtained through chemical bath deposition method. Structural and optical properties of as deposited and annealed samples were investigated by X-ray Diffraction and spectrophotometer. The as deposited thin films were in nanocrystalline, with lots of strain and a blue shift of optical band gap. After annealing, the crystal grain gained, the strain eased and optical band gap enlarged. And it suggested that annealing can ease the quantum effect of chemical bath deposited ZnSe thin films.


2019 ◽  
Vol 26 (03) ◽  
pp. 1850158 ◽  
Author(s):  
MARYAM MOTALLEBI AGHGONBAD ◽  
HASSAN SEDGHI

Zinc Oxide thin films were deposited on glass substrates by sol–gel spin coating method. Zinc acetate dihydrate, 2-methoxyethanol and monoethanolamine were used as precursor, solvent and stabilizer, respectively. Zinc acetate dihydrate was used with different molar concentrations of 0.15, 0.25 and 0.5 M. Optical properties of ZnO thin films such as dielectric constants, absorption coefficient, Urbach energy and optical band gap energy were calculated by spectroscopic ellipsometry (SE) method. The effect of zinc acetate concentration on optical properties of ZnO thin films is investigated. ZnO thin film with Zn concentration of 0.25 M had the highest optical band gap. Wemple DiDomenico oscillator model was used for calculation of the energy of effective dispersion oscillator, the dispersion energy, the high frequency dielectric constant, the long wavelength refractive index and the free carrier concentration.


2005 ◽  
Vol 905 ◽  
Author(s):  
B. Yang ◽  
Y. M. Lu ◽  
C. Neumann ◽  
A. Polity ◽  
C. Z. Wang ◽  
...  

AbstractDelafossite-type CuAlO2 thin films have been deposited by radio frequency (RF) reactive sputtering on sapphire using a CuAlO2 ceramic target. A study of structural and optical properties was performed on films of varying deposition parameters such as substrate temperature and oxygen partial pressure and also post annealing. The crystalline phase in the films was identified to be the delafossite structure by x-ray diffraction. The optical properties, such as the wavelength dependence of the transmittance and the band gap, were determined. The average transmittance is 80% in the wavelength range of 400-1500 nm and the band gap is 3.81 eV.


2012 ◽  
Vol 616-618 ◽  
pp. 1773-1777
Author(s):  
Xi Lian Sun ◽  
Hong Tao Cao

In depositing nitrogen doped tungsten oxide thin films by using reactive dc pulsed magnetron sputtering process, nitrous oxide gas (N2O) was employed instead of nitrogen (N2) as the nitrogen dopant source. The nitrogen doping effect on the structural and optical properties of WO3 thin films was investigated by X-ray diffraction, transmission electron microscopy and UV-Vis spectroscopy. The thickness, refractive index and optical band gap energy of these films have been determined by analyzing the SE spectra using parameterized dispersion model. Morphological images reveal that the films are characterized by a hybrid structure comprising nanoparticles embeded in amorphous matrix and open channels between the agglomerated nanoparticles. Increasing nitrogen doping concentration is found to decrease the optical band gap energy and the refractive index. The reduced band gaps are associated with the N 2p orbital in the N-doped tungsten oxide films.


2018 ◽  
Vol 14 (2) ◽  
pp. 5624-5637
Author(s):  
A.A. Attia ◽  
M.M. Saadeldin ◽  
K. Sawaby

Para-quaterphenyl thin films were deposited onto glass and quartz substrates by thermal evaporation method. p-quaterphenyl thin films wereexposed to gamma radiation of Cobat-60 radioactive source at room temperature with a dose of 50 kGy to study the effect of ?-irradiation onthe structure and the surface morphology as well as the optical properties of the prepared films. The crystalline structure and the surface morphology of the as-deposited and ?-irradiated films were examined using the X-ray diffraction and the field emission scanning electron microscope. The optical constants (n & k) of the as-deposited and ?-irradiated films were obtained using the transmittance and reflectance measurements, in the wavelength range starting from 250 up to 2500 nm. The analysis of the absorption coefficient data revealed an allowed direct transition with optical band gap of 2.2 eV for the as-deposited films, which decreased to 2.06 eV after exposing film to gamma irradiation. It was observed that the Urbach energy values change inversely with the values of the optical band gap. The dispersion of the refractive index was interpreted using the single oscillator model. The nonlinear absorption coefficient spectra for the as-deposited and ?-irradiated p-quaterphenyl thin films were obtained using the linear refractive index.


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