Growth of α-Ga2O3 on α-Al2O3 by conventional molecular-beam epitaxy and metal–oxide-catalyzed epitaxy

Abstract

We report the growth of α-Ga2O3 on m-plane α-Al2O3 by conventional plasma-assisted molecular-beam epitaxy and In-mediated metal–oxide-catalyzed epitaxy (MOCATAXY). We report a growth rate diagram for α-Ga2O3( 101¯0 ), and observe (i) a growth rate increase, (ii) an expanded growth window, and (iii) reduced out-of-plane mosaic spread when MOCATAXY is employed for the growth of α-Ga2O3. Through the use of In-mediated catalysis, growth rates over 0.2 μm h−1 and rocking curves with full width at half maxima of Δω ≈ 0.45° are achieved. Faceting is observed along the α-Ga2O3 film surface and explored through scanning transmission electron microscopy.