Phase transformations during the annealing of Ga2O3 films

• Published in: Kondensirovannye sredy i mežfaznye granicy Vol. 25; no. 4; pp. 557 - 563
• Main Authors: Osipov, Andrei V., Sharofidinov, Shukrillo Sh, Kremleva, Arina V., Smirnov, Andrey M., Osipova, Elena V., Kandakov, Andrei V., Kukushkin, Sergey A.
• Format: Journal Article
• Language: English
• Published: 12.10.2023
• ISSN: 2687-0711
• DOI: 10.17308/kcmf.2023.25/11479

       A growth technique has been developed to obtain the three main crystalline phases of Ga2O3, namely: a-phases, e-phases, and b-phases using hybrid vapour phase epitaxy (HVPE). The substrate temperatures and precursor fluxes were determined at which only the a-phase, only the e-phase, or only the b-phase were deposited. It was found that the annealing of the metastable a- and e-phases led to completely different results. The e-phase quickly transforms into the stable b-phase as a result of annealing, while the a-phase, upon annealing, transforms into an intermediate amorphous phase, after which it peels off and is destroyed. The obtained result is explained by the fact that the reconstructive phase transition from the a-phase into the b-phase is accompanied by too large an increase in density (~10%), leading to enormous elastic stressesand, consequently, an increase in the height of the phase transition barrier