Effect of laser wavelength on Indium Trioxide (In2O3) thin films deposited by pulsed laser deposition method

Abstract

The pulse laser deposition (PLD) technique was used to prepare and deposit indium trioxide (In2O3) as thin films with a nanocrystalline structure on the silicon porous and quartz substrates. The laser wavelength effect on the optical and structure properties of these films was investigated. The PLD technique is accomplished using the following constant parameters: temperature (300°C), frequency (3 Hz), number of pulses (250 pulses), and voltage (900 V), but with three different laser wavelengths: 1064 nm, 532nm, and 355nm. To characterize and analyze these nanostructure thin films Ultra-Violet Visible (UV-vis) and X-ray diffraction (XRD) were used. The UV-vis analysis shows that: the laser wavelength does not have a significant effect on the transmission, absorption, and energy band gap values, it can be seen that when the laser wavelength increases the transmission values of thin films increase. While the values of absorption and energy band gap appear the random behavior with this increase. Also, it can be noted the laser wavelength does not have a significant effect on the refractive index values, since it achieves close values when the three different laser wavelengths were used. The XRD analysis shows that: the structure of In2O3 thin film will be purer and more crystalline with increasing laser wavelength because the intensity of phase 2θ at values of 31.8°, 34.06° and 63.48° correspond to (222), (400), and (662) planes increased when the laser wavelength increases.