High crystal quality β-Ga2O3 epitaxial films grown on porous n-GaN substrates

In this paper, beta-Ga2O3 films were grown on GaN (0001) substrates before and after electrochemical etching via MOCVD. XRD results showed that the beta-Ga2O3 film was grown on the GaN substrate etched in oxalic acid solution at 9 V and under the substrate temperature of 950 degrees C presented the best crystal quality. The epitaxial relationship between the beta-Ga2O3 film and GaN substrate was beta-Ga2O3 ((2) over bar 01)parallel to GaN (0002) with beta-Ga2O3 <102>parallel to GaN < <(1)over bar>2 (1) over bar0>. The optimization of the crystallization quality of Ga2O3 films by the porous structure of the substrate should be attributed to the reduction of threading dislocations (TDs) caused by stacking faults (SFs) and inclined facets.