Ayu Wazira Azhari
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Preferred name
Ayu Wazira Azhari
Official Name
Ayu Wazira, Azhari
Alternative Name
Ayu, A. W.
Azhari, Ayu W.
Main Affiliation
Scopus Author ID
24450001400
Researcher ID
ABA-7808-2020

Research Output
Now showing 1 - 4 of 4
  • Publication
    Annealing effects on Polycrystalline Silicon Germanium (SiGe) thin films grown on nanostructured silicon substrates using thermal evaporation technique
    (Universiti Malaysia Perlis (UniMAP), 2022-10)
    Ayu Wazira Azhari
    ;
    Eop, T. S.
    ;
    Dewi Suriyani Che Halin
    ;
    Uda Hashim
    ;
    Sopian, K.
    ;
    Zaidi, S. H.
    Polycrystalline SiGe thin films have been formed after thermal annealing of formerly vacuum evaporated a-Ge layers. The a-Ge thin films were deposited onto nanostructured Si substrates via low-cost thermal evaporation method. Then, the films were annealed in a furnace at temperatures ranging from 400 °C to 1000 °C resulting in crystal growth of the SiGe layers. In general, the annealing temperature for polycrystalline SiGe is between 600 °C – 800 °C. The crystalline structure of the SiGe layer is improved as a function of increased temperature. This is shown by the low FWHM of about 5.27 as compared to the commercially available Ge substrates where the FWHM value is about 5.06. This method also produces more relax Ge layer where the strain value is 0.261.
  • Publication
    Effect of temperature and amount of Ag on TiO₂ thin film synthesised via sol–gel method
    (Springer, 2025-02)
    Dewi Suriyani Che Halin
    ;
    Kamrosni Abdul Razak
    ;
    Dharshini Karikalan
    ;
    Lukasz Kaczmarek
    ;
    Sebastian Miszczak
    ;
    Ayu Wazira Azhari
    ;
    Mohd Arif Anuar Mohd Salleh
    ;
    Nur Izzati Muhammad Nadzri
    ;
    Juyana A. Wahab
    ;
    Mohd. Mustafa Al Bakri Abdullah
    TiO₂ sol was produced via the sol–gel method with different amounts of AgNO₃ as the source of Ag. The Ag/TiO₂ thin film was obtained by spin coating and was annealed at various annealing temperatures (300°C, 400°C and 500°C) for 1 h. The effect of different amounts of AgNO₃ and different annealing temperatures on the TiO₂ thin films was studied by characterising the phase composition, surface morphology and water contact angle. Results from the x-ray diffraction (XRD) pattern show that with the addition of AgNO₃, Ag/TiO₂ can be formed at low annealing temperatures (300°C). At increased annealing temperatures (400°C and 500°C) and amounts of AgNO₃ (1.0 ml and 1.5 ml), Ag₂O and Ag₃O4 phases were observed. Flakes or flaky islands were formed on the thin film due to thermal expansion mismatch between the film and substrate, residual stress within the film or the release of volatile species when annealed at a low temperature of ⁓300°C. Increasing the temperature to 500°C resulted in the growth and coalescence of the flaky islands by the surface diffusion of adsorbed atoms (adatoms) and their annexation to the surface of existing nuclei. The water contact angle provides valuable insight into the surface interactions between water droplets and the surface of Ag/TiO₂ thin films. It was found that at 1.5 ml AgNO₃, the increased annealing temperature from 300°C to 500°C decreased the water contact angle of Ag/TiO₂ thin films from 83.86° to 34.62°, forming superhydrophilic properties, which indicated its excellent potential as a photocatalyst.
  • Publication
    Microstructure evolution of Ag/TiO2 thin film
    ( 2021)
    Dewi Suriyani Che Halin
    ;
    Kamrosni Abdul Razak
    ;
    Mohd Arif Anuar Mohd Salleh
    ;
    Mohd Izrul Izwan Ramli
    ;
    Mohd. Mustafa Al Bakri Abdullah
    ;
    Ayu Wazira Azhari
    ;
    Kazuhiro Nogita
    ;
    Hideyuki Yasuda
    ;
    Marcin Nabiałek
    ;
    Jerzy J. Wysłocki
    Ag/TiO2 thin films were prepared using the sol-gel spin coating method. The microstructural growth behaviors of the prepared Ag/TiO2 thin films were elucidated using real-time synchrotron radiation imaging, its structure was determined using grazing incidence X-ray diffraction (GIXRD), its morphology was imaged using the field emission scanning electron microscopy (FESEM), and its surface topography was examined using the atomic force microscope (AFM) in contact mode. The cubical shape was detected and identified as Ag, while the anatase, TiO2 thin film resembled a porous ring-like structure. It was found that each ring that coalesced and formed channels occurred at a low annealing temperature of 280 °C. The energy dispersive X-ray (EDX) result revealed a small amount of Ag presence in the Ag/TiO2 thin films. From the in-situ synchrotron radiation imaging, it was observed that as the annealing time increased, the growth of Ag/TiO2 also increased in terms of area and the number of junctions. The growth rate of Ag/TiO2 at 600 s was 47.26 µm2/s, and after 1200 s it decreased to 11.50 µm2/s and 11.55 µm2/s at 1800 s. Prolonged annealing will further decrease the growth rate to 5.94 µm2/s, 4.12 µm2/s and 4.86 µm2/s at 2400 s, 3000 s and 3600 s, respectively.
      20  1
  • Publication
    Annealing effects on polycrystalline silicon germanium (SiGe) thin films grown on nanostructured silicon substrates using thermal evaporation technique
    ( 2022-10)
    Ayu Wazira Azhari
    ;
    Eop, T. S.
    ;
    Dewi Suriyani Che Halin
    ;
    Sopian, K.
    ;
    Uda Hashim
    ;
    Zaidi, S. H.
    Polycrystalline SiGe thin films have been formed after thermal annealing of formerly vacuum evaporated a-Ge layers. The a-Ge thin films were deposited onto nanostructured Si substrates via low-cost thermal evaporation method. Then, the films were annealed in a furnace at temperatures ranging from 400 °C to 1000 °C resulting in crystal growth of the SiGe layers. In general, the annealing temperature for polycrystalline SiGe is between 600 °C – 800 °C. The crystalline structure of the SiGe layer is improved as a function of increased temperature. This is shown by the low FWHM of about 5.27 as compared to the commercially available Ge substrates where the FWHM value is about 5.06. This method also produces more relax Ge layer where the strain value is 0.261.
      1  15