First-principle investigation of monoclinic (Al _x In _y Ga _{1− x − y} ) ₂ O ₃ quaternary alloys

Abstract

Abstract First-principle density functional theory calculations were performed to explore electronic and structural properties of β -(Al x In y Ga 1− x − y ) 2 O 3 quaternary alloys with both Al-content ( x ) and In-content ( y ) ranging from 0% to 18.75%. The β -(Al x In y Ga 1− x − y ) 2 O 3 quaternary alloys exhibit indirect band gap property with the bandgap energy varying from 4.432 to 5.171 eV. Electron effective masses are also presented for β -(Al x In y Ga 1− x − y ) 2 O 3 quaternary alloys, showing a general reduction with In-content increases but a general increment with Al-content increases in the material. Further analysis indicates the possibility of achieving lattice-matched or near-lattice-matched β -(Al x In y Ga 1− x − y ) 2 O 3 / β -Ga 2 O 3 structures system, which is critical for high performance field effect transistor and deep ultraviolet photodetector applications. Our work shows that the β -(AlInGa) 2 O 3 alloys with proper tuning of Al- and In-content have strong potential to be used as part of the epitaxial layers for β -Ga 2 O 3 -based material system.