【Domestic Papers】Wuhan University —— Theoretical insights into the interface engineering of β-Ga₂O₃ devices with ferroelectric HfO₂ gate dielectric: Impact of polarization direction

      Researchers from the Wuhan University have published a dissertation titled " Theoretical insights into the interface engineering of β-Ga₂O₃ devices with ferroelectric HfO₂ gate dielectric: Impact of polarization direction " in Surfaces and Interfaces.

Abstract

      Using ferroelectric materials is an important strategy to achieve a high interfacial density of carrier between ferroelectric materials and ultrawide bandgap semiconductor materials integrated into high carrier density electronic devices. This study investigates the structural and electronic properties of ferroelectric HfO₂ (fe-HfO₂)/β-Ga₂O₃ heterostructures under the influence of polarization direction through first-principles calculations. The results display that the stable heterostructures composed of either fe-HfO₂ (001) or fe-HfO₂ (00-1) gate dielectric layers and the β-Ga₂O₃ (-201) substrates show a type-II band alignment. The opposite polarization directions of fe-HfO₂ lead to the formation of a high density of electrons in the fe-HfO₂ (001)/β-Ga₂O₃ heterostructure and a high density of holes in the fe-HfO₂ (00-1)/β-Ga₂O₃ heterostructure. This study provides valuable insights into the interfacial properties of fe-HfO₂/β-Ga₂O₃ heterostructures and will guide the development of high carrier density β-Ga₂O₃ devices utilizing fe-HfO₂ as a gate dielectric.