Transparent MIS capacitors on plastic substrates fabricated by high-frequency ultrasonic spray pyrolysis

In this article, the fabrication and characterization of transparent metal-insulator-semiconductor (MIS) capacitors on plastic substrates are presented. Zinc oxide and indium tin oxide films were used as semiconductor layer and electrode, respectively. The thin films were deposited by a home-made high-frequency ultrasonic spray pyrolysis deposition system. Polyethylene terephthalate is used as plastic substrate. The maximum temperature of the process was 200°C. The MIS capacitors exhibit above 70% of transparency and operate at ±1 V. Therefore, the transparent devices are compatible with low-power electronics. Moreover, the thin films were characterized by Fourier transform infrared spectroscopy, X-ray diffraction, field emission scanning electron microscope and Raman spectroscopy.