β-(Al0.18Ga0.82)2O3/Ga2O3 Double Heterojunction Transistor With Average Field of 5.5 MV/cm

Concepts

SemiconductorsSemiconductor TechnologyElectrical EngineeringAverage FieldEngineeringWide-bandgap SemiconductorPhysicsNanoelectronicsApplied PhysicsQuantum MaterialsComposite Dielectric LayerGallium OxidePeak Electric FieldPower SemiconductorsMicroelectronicsHigh Average FieldsSemiconductor Device

Abstract

Maintaining high average fields between the gate and drain is imperative in achieving near theoretical performance in ultra-wide band gap semiconductors like β-Ga 2 O 3 . In this letter we report on a field management strategy to reduce the peak electric field at the drain side corner of the gate by using a composite dielectric layer consisting of an extreme permittivity dielectric like BaTiO 3 and a low- κ dielectric like SiO 2 overlapped over the gate electrode. Using this strategy in β-(Al 0.18 Ga 0.82 ) 2 O 3 / Ga 2 O 3 double heterojunction field effect transistor, we achieved a record average breakdown field of 5.5 MV/cm at a gate-drain spacing of 1.15 μm along with an improved power figure of merit of 408 MW/cm 2 . The reported works shows the effectiveness of integrating extreme dielectric materials with ultra-wide band gap semiconductors in significantly improving breakdown performance.