Low temperature growth of Ga2O3 films on sapphire substrates by plasma assisted pulsed laser deposition

Monoclinic β-Ga2O3 thin films with (-201) orientation have been fabricated at substrate temperature as low as 200 °C by using plasma assisted pulsed laser deposition. The film showed high transmittance of over 80% with clear fringes in the wavelength range from 300 to 1000 nm. Structural characterization from X-ray diffraction as well as Raman spectra analysis demonstrated the monoclinic structure of the films. β-Ga2O3 film deposited at 200 °C showed similar growth rate as well as optical bandgap values with films grown at higher temperatures from 300 to 500 °C, indicating the enhanced reaction between Ga and oxygen species during the deposition process with the assistant of plasma at low temperature. The low temperature growth of β-Ga2O3 film paves the way to be compatible with the established lithography of semiconductor microfabrication processes.