N2O grown high Al composition nitrogen doped β-(AlGa)2O3/β-Ga2O3 using MOCVD

We report on the MOCVD growth of smooth (010) (AlxGa1–x)2O3 and (100) (AlyGa1–y)2O3 epitaxial films β-Ga2O3 substrates with orientations, respectively, using N2O for oxidation. High resolution x-ray diffraction was used to evaluate phase purity strain characteristics (AlGa)2O3 layers estimate Al composition. The incorporation efficiency into depends process conditions, including chamber pressure, temperature, gas concentration. Layers grown at lower reactor pressure substrate temperature higher concentration showed incorporation. Pure beta a record high composition x = 30% film an up y 45% realized by introducing ∼18% mole fraction reactor. β-(AlGa)2O3/β-Ga2O3 superlattice structures 5% were also demonstrated both orientations. When is introduced reactor, pure γ-phase substrates. In contrast, substrate, are β-phase, but two separate compositions owing local segregation. nitrogen doping β-(AlxGa1–x)2O3 [N] ranging 6 × 1017–2 1019 cm−3 achieved N2O. Higher lead N results show that as oxygen source can content β-(AlGa)2O3, which paves way realization efficient power devices, such modulation-doped field effect transistors.