Temperature dependence of Raman scattering in β-(AlGa)2O3 thin films

Abstract

We report a detailed investigation on temperature-dependent Raman scattering of β-(AlGa)2O3 thin films with different Al content (0-0.72) under the temperature range of 77-300 K. The temperature-dependent Raman shifts and linewidths of the phonon modes were obtained by employing Lorentz fitting. The linewidths broadening of phonon modes with the temperature can be well explained by a model involving the effects of thermal expansion, lattice-mismatch-induced strain, and decay of optical phonon into two and three phonons. It is clearly demonstrated dependence of the linewidths and decay process on the Al content in β-(AlGa)2O3 thin films, which can provide an experimental basis for realization of (AlGa)2O3-based optoelectronic device applications.

Electronic properties and stability of M2O3 (M = Al, Ga, In) and alloy (MxGa1‐x)2O3 in α and β phases: A theoretical study

“…For alloy (Al x Ga 1-x ) 2 O 3 , the stable phase inversion point is at x = 0.69, that is, when the composition of Al 2 O 3 is greater than 69%, the stable phase of (Al x Ga 1-x ) 2 O 3 changes from the monoclinic phase to the corundum phase. This calculated result is very close to the experimental data (x = 0.72-0.76) 24,54 . The small discrepancy might come from the difference between the complicated experimental conditions and the relatively simple calculation hypothesis, that is, the synthesized alloy structure in the experiments might not be a so perfect cation ordered alloy structure.…”

Effect of Different Parameters on Raman Scattering Released from Nb2O5 Nanostructures Prepared via PLD Technique

“…Other bands weakly appeared at abound 460.1 cm -1 referring to the framework vibration of oxygen metal oxide structures. A very close indication was in ref [22]. The observed broadening in Raman bands can be attributed to the phonon linewidth modes as a function of temperature, besides other parameters, including the thermal expansion and the strain caused by the lattice mismatch.…”

Raman Spectroscopic Characterization of Chemical Bonding and Phase Segregation in Tin (Sn)-Incorporated Ga2O3

“…41,54 With an increase in dopant comes an increase in the amount of foreign atoms entering the crystal lattice of β-Ga 2 O 3 , which forms a ternary solid solution. 54 The broadening of the peak at 652 cm −1 may be explained by the same principle, as x = 0.25 and 0.30 concentration is the threshold amount for solute atoms to enter the lattice. The atomic radii mismatch between Ga 3+ and Sn 2+ is large enough to contribute to this peak broadening.…”