Figure 1. (a) 2θ-ω scan recorded around the α-Al2O3 0006 reflection. Rocking curve ω scans recorded on the (b) α-Ga2O3 0006 and (c) α-Ga2O3 10-14 reflections. RSMs around the (d) α-Al2O3 0006 and (e) α-Al2O3 10-110 reflections.

Figure 2. (a) ADF-STEM and (b) HR-TEM image of the sample observed along the α-Al2O3 〈11-20〉 zone-axis. In inset, ABSF-filtered (average background subtraction filter) image of the interface region indicated with a square in (b).

Figure 3. SED of the Ga2O3 film observed near the α-Al2O3 〈11-20〉 zone-axis. (a) Composite diffraction contrast image formed plotting the intensity of selected reflections as a function of probe position. Green corresponds to reflections in the α-Ga2O3 〈11-20〉 zone-axis pattern and red corresponds to additional reflections identified in the data. Inset shows the intensity of the direct beam revealing the full extent of the film including non-diffracting components. Representative diffraction patterns (b) from the α-Ga2O3 columns, (c-d) from the tips which are most likely ε-Ga2O3.