Growth and Characterization of (InxGa1-x)2O3 Thin Films Grown by Pulsed Laser Deposition
Abstract
Silicon has been an important material in the integrated circuit (IC) technology and is a commonly used elemental semiconductor. However, silicon has limitations in its operating voltage, temperature and switching frequency. Furthermore, being an indirect bandgap semiconductor, it is unsuitable for optoelectronic device applications. Wide bandgap semiconductors that include GaN and SiC is being used for power application but their breakdown field is limited. A new generation of power semiconductor devices based on materials having a larger breakdown field will help increase the efficiency of alternative electric energy transmission and generation. Due to its excellent thermal and chemical stability, beta-gallium oxide (β-Ga2O3) is a promising material for high breakdown, high-power devices. It’s large direct bandgap of 4.9 eV is predicted to have a high breakdown electric field of 8 MV/cm for fabricated electronic devices. The large bandgap of β-Ga2O3 makes it transparent from the visible to UV wavelengths and can be alloyed with In2O3 to provide tunable bandgaps.
The growth of (InxGa
The percentage transmittance of the films is determined by ultraviolet visible spectroscopy with the films exhibiting large transmittance values in the visible region. The extracted bandgap was found to decrease with increase in indium content as expected.