Structural Properties and Raman Spectra of Micron-Thick <i>β</i>-Ga₂O₃ Films Deposited on SiC/Porous Si/Si Substrates

The possibility of expanding the element base of optoelectronics and power electronics by using β -Ga 2 O 3 motivates the search for efficient methods for growing its high-quality films. Here, β -Ga 2 O 3 films with thicknesses of 1.15 and 2.25 μm were deposited on SiC/porous Si/Si substrates using high-frequency magnetron sputtering and characterized by scanning electron microscopy, X-ray diffraction (XRD), and micro-Raman spectroscopy techniques. The films were composed of β -Ga 2 O 3 crystallites with an average size of 62 and 109 nm, preferentially oriented along [100] direction. The relative increase of their lattice parameters with respect to single crystal ones was no more than 1.5 × 10 –3 for the c parameter. The small strain values of about 1 × 10 –3 calculated from the XRD patterns were verified by the absence of any significant changes in phonon modes’ parameters in the β -Ga 2 O 3 film Raman spectra.