[01] M. Vishwas, Department of Physics, Government Science College (Autonomous), Bangalore, India. [02] K. Narasimha Rao, Department of Instrumentation and Applied Physics, Indian Institute of Science, Bangalore, India. [03] Ashok M. Raichur, Department of Materials Engineering, Indian Institute of Science, Bangalore, India.

Zinc oxide (ZnO) thin films were prepared on p-silicon (100) substrates by the sol-gel technique using zinc acetate dehydrate as a precursor material with and without surfactant. The films were heat treated by microwave-assisted method and annealed at various temperatures in ambient air. Different nano-structures were obtained by the varying annealing conditions. The structural characterization of ZnO films were carried out using x-ray diffraction (XRD) and scanning electron microscopy (SEM). The metal-oxide-semiconductor (MOS) capacitors were fabricated using ZnO film. The electrical properties of ZnO films with surfactant were studied from current-voltage (I-V), dissipation-voltage (D-V) and capacitance-voltage (C-V) characteristics and found that the dielectric constant of ZnO film increased with the additive surfactant. The leakage current density in ZnO film decreased and resistivity increased with surfactant.

ZnO, Sol-Gel, Thin Films, Nano-Structures, MOS-Capacitor

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