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Ceramic oxide thin films are an important material, with applications in many areas of science and technology. Titanium oxide (TiO2) is also a well-known and important material for applications such as gas sensors [1], photocatalysis materials [3], and electrochemicals [1], due to its self-cleaning [2], good corrosion resistance and biocompatibility. Atomic Layer Deposition (ALD) is a nanotechnology tool that is used for the deposition of nanostructured thin films. The unique advantage of ALD is the self-limiting film growth mechanism, which offers attractive properties, simple and accurate film thickness control, sharp interfaces, uniformity over large areas, excellent conformality, good reproducibility, a multilayer processing capability, and high quality films at low temperatures [3, 4]. TiO2 thin films were grown using TTIP (Titanium isopropoxide) ALD on silicon wafers, glass slides, and stainless steel plates in order to study the effect of substrates on the growth of TiO2. In order to achieve the desired advantages of using TTIP, a series of experiments were performed to study the growth mechanism of TiO2 thin films using TTIP and H2O by ALD.

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TiO2/ZnO nanostructured thin films were grown using sol-gel route. The nanostructured thin films were deposited by dip coating method on glass substrates and calcined at different temperatures (400°C, 500°C, and 600°C). The thin films were characterized using X-Ray Diffraction method (XRD), Atomic Force Microscope (AFM), and Ultraviolet Visible Spectroscopy (UV-Vis). The XRD pattern showed that the crystallinity of the calcined thin films had improved when the calcination temperature was increased. According to AFM observation and analysis, surface roughness of the thin films controllable via growth condition. While the transmittance percentage of ultraviolet by Titanium Dioxide (TiO2) thin films through UV-Vis could be improved by combination with Zinc Oxide (ZnO). The percentage of transmittance by TiO2/ZnO nanostructured thin films continue to improve as the calcination temperature were increased.

Thin film has been extensively study due to better structural, surface morphology, and optical properties. The combination of two materials will enhance the properties of thin film. In this study, TiO2/ZnO thin films were deposited on glass substrates via sol-gel method. TiO2 acts as pre-deposited thin film with calcination temperatures at 400 °C, 500 °C, and 600 °C. The post-deposition of TiO2/ZnO thin films were calcined at 500 °C and 600 °C. TiO2 sol-gel was synthesis from titanium (IV) butoxide and butanol as the precursor, while ZnO sol-gel was synthesis from zinc acetate dehydrate and isopropanol as the precursor. The TiO2/ZnO thin films were characterized by X-ray diffraction (XRD), atomic force microscope (AFM), and ultraviolet visible spectroscopy (UV-Vis). The effect of calcination temperature and pre-deposited TiO2 thin films show difference results of bilayer thin films. The XRD analysis shows all TiO2/ZnO thin films growth with TiO2 anatase crystalline phase at orientation (1 0 1) and ZnO zincite phase at orientation (1 0 1). The structural properties of TiO2/ZnO thin films were improved by controlling the calcination temperature. Based on AFM analysis, the RMS value for TiO2/ZnO decreases as the calcination temperature increased. The compacted and dense surface roughness were controlled by the temperature. Meanwhile, the percentage of thin film ultraviolet transmittance can be enhanced with combination of two materials, TiO2 and ZnO. Therefore, the pre-deposited layer of thin film with influenced by calcination temperature will improve the crystallinity, surface morphology, and optical properties of TiO2/ZnO thin films.

Metal oxide semiconductor materials have shown a great potential in the fabrication of heterojunction thin film due to its improved properties for photovolatic mechanism in solar cell application. In this work, p-(111)-Cu 2 O based heterostructure was successfully developed with uniformity and highly oriented n-TiO 2 /(002)-ZnO bilayer thin film in order to overcome improper electron mobility between the heterointerface of n and p-type layer by optimizing several properties. n-TiO 2 /ZnO bilayer acts as window layer deposited on FTO substrate by using sol-gel spin coating method. The crystallize size and transmittance spectrum of n-TiO 2 thin film was improved after n-ZnO was coated onto TiO 2 thin film. Meanwhile, cyclic voltammetry (CV) measurement was carried out and potential deposition of −0.4 V vs Ag/Cl at 40 °C was acquired. p-Cu 2 O which acts as absorbing layer was deposited onto n-TiO 2 /ZnO bilayer by using electrodeposition technique. The successful fabrication of n-TiO 2 /ZnO/p-Cu 2 O heterostructure were confirmed by the existence of all peaks on the XRD spectrum. Two strong absorption edges observed and the merged shape of p-Cu 2 O grain with other layer leads to the surface flatness improvement. The optical energies of n-TiO 2 /ZnO bilayer and p-Cu 2 O thin film are estimated as 3.15 and 1.75 eV, respectively. The structural, morphological, optical, and topological properties of thin films were characterized using X-ray diffraction, Field emission-scanning electron microscope, Ultraviolet-visible spectroscopy, and Atomic force microscopy, respectively.

Tungsten carbide-based composite / cermet coatings have been deposited to improve metal properties such as hardness, corrosion resistance, and wear resistance. In this study, the evaluation of two deposition methods, which are high velocity oxy-fuel (HVOF) and electrodeposition (ED) is done to compare their performance as metal protection from corrosion and wear. The HVOF powder was deposited using oxygen and natural compress gas and sprayed at 700 m/s. Watt’s Bath was used as an electrolyte in ED coating method. The corrosion and wear behavior was assessed using electrochemical and weight loss methods, respectively. The HVOF coating shows more positive corrosion potential, Ecorr at -0.75 V showing higher corrosion resistance than the ED coating at 1.15 V. The wear rate for HVOF coating is lower than the ED coating at 0.0001 g/m compared to ED coating at 0.0002 g/m. In can be concluded that the HVOF coating has higher wear and corrosion resistance compared to ED coating.

ALD is a precision growth technique that can deposit either amorphous or polycrystalline thin films on a variety of substrates. The difference in substrate can cause a variation in the ALD process, even it is carried out using the same reactants and deposition conditions [1]. TiO2thin films were grown using TTIP (Titanium isopropoxide) ALD on silicon wafers, glass slides, and stainless steel plates in order to study the effect of substrates on the growth of TiO2with 3,000 deposition cycles, at 300°C.The thin films were analyzed using Xray Diffraction (XRD), Raman Spectroscopy, Atomic Force Microscope (AFM) and Spectroscopic Ellipsometer. From XRD analysis were indicates the main peak for anatase (101) (2θ= 25.3) was observed from the XRD patterns for TiO2on all substrates. The results show that crystalline TiO2thin films can easily grow on a crystal substrate rather than on an amorphous substrate.