In this work AZO and CZTS thin films were prepared using solution process for solar cell Applications. Aluminum doped zinc oxide (AZO) as transparent electrode to be used for solar cells were deposited on pristine and self assembled monolayer (SAMs) modified glass substrates by chemical spray pyrolysis technique. SAMs with different terminal functional groups such as – CH3, – CF3 and -NH2 were fabricated on glass substrates. The measurement of different parameters showed that modifying the surface of the substrate with the different SAMs exhibits an excellent nucleation site for the crystal growth of the AZO thin film. We demonstrated that crystallinity of AZO films can be improved using self assembled monolayers (SAMs) modified glass substrate. Parameters that are used to verify the quality of the film such as structural, electrical and optical properties were performed by XRD, SEM, Hall measurement and UV-Vis spectrum measurements. From the results we observed that SAM with –CH3 group remarkably improves the quality of the film, while the other groups improve the quality moderately. Our finding suggests a alternative approach of improving the crystallinity of AZO film with spray pyrolysis technique.
CZTS nanoparticle thin films were prepared by spray pyrolysis technique using different solvents. The characterization result reveals that there are many secondary phases rather than pure CZTS and the composition is very far from the stoichiometris ratio. Of course there was a very good improvemment while we were use a mixture of ethylene glycol and methanol solvents. But film thickness is not sufficient for the material to use for solar cell applications. This might be due to the high boiling point of ethylene glycol which is not convenient for arseol generation for the spray system.
Then after we switched to a technique called solvothermal method without vacuum system. Nearly stoichiometric quaternary Cu2ZnSnS4 (CZTS) nanocrystal thin films were successfully synthesized using a low-cost and high reproducibility method. Properties such as crystal structure, morphology, and optical properties of the CZTS nanocrystal thin films were characterized by X-ray diffraction (XRD), Raman spectra, scanning electron microscope (SEM), energy dispersive spectrometer (EDS) and ultraviolet-visible (UV–vis) spectrophotometry. The results showed that the synthesized CZTS nanocrystal thin films had almost single phase, good crystallinity and nearly stoichiometric composition. The X-ray diffraction patterns of (112), (220) and (312) planes showed that the CZTS nanocrystal thin films had a kesterite structure. The UV–vis absorption spectra showed that CZTS nanocrystal thin films had strong absorption in the visible light region. Moreover, the prepared products showed the morphology of nanocrystal thin films \and their energy band gaps 1.52 eV made them promising candidates as absorber materials for photovoltaic applications.

In this work AZO and CZTS thin films were prepared using solution process for solar cell Applications. Aluminum doped zinc oxide (AZO) as transparent electrode to be used for solar cells were deposited on pristine and self assembled monolayer (SAMs) modified glass substrates by chemical spray pyrolysis technique. SAMs with different terminal functional groups such as – CH3, – CF3 and -NH2 were fabricated on glass substrates. The measurement of different parameters showed that modifying the surface of the substrate with the different SAMs exhibits an excellent nucleation site for the crystal growth of the AZO thin film. We demonstrated that crystallinity of AZO films can be improved using self assembled monolayers (SAMs) modified glass substrate. Parameters that are used to verify the quality of the film such as structural, electrical and optical properties were performed by XRD, SEM, Hall measurement and UV-Vis spectrum measurements. From the results we observed that SAM with –CH3 group remarkably improves the quality of the film, while the other groups improve the quality moderately. Our finding suggests a alternative approach of improving the crystallinity of AZO film with spray pyrolysis technique.
CZTS nanoparticle thin films were prepared by spray pyrolysis technique using different solvents. The characterization result reveals that there are many secondary phases rather than pure CZTS and the composition is very far from the stoichiometris ratio. Of course there was a very good improvemment while we were use a mixture of ethylene glycol and methanol solvents. But film thickness is not sufficient for the material to use for solar cell applications. This might be due to the high boiling point of ethylene glycol which is not convenient for arseol generation for the spray system.
Then after we switched to a technique called solvothermal method without vacuum system. Nearly stoichiometric quaternary Cu2ZnSnS4 (CZTS) nanocrystal thin films were successfully synthesized using a low-cost and high reproducibility method. Properties such as crystal structure, morphology, and optical properties of the CZTS nanocrystal thin films were characterized by X-ray diffraction (XRD), Raman spectra, scanning electron microscope (SEM), energy dispersive spectrometer (EDS) and ultraviolet-visible (UV–vis) spectrophotometry. The results showed that the synthesized CZTS nanocrystal thin films had almost single phase, good crystallinity and nearly stoichiometric composition. The X-ray diffraction patterns of (112), (220) and (312) planes showed that the CZTS nanocrystal thin films had a kesterite structure. The UV–vis absorption spectra showed that CZTS nanocrystal thin films had strong absorption in the visible light region. Moreover, the prepared products showed the morphology of nanocrystal thin films \and their energy band gaps 1.52 eV made them promising candidates as absorber materials for photovoltaic applications.

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