Japanese Journal of Applied Physics · 2018 · 10 citations · 23 references
EngineeringMaterials EngineeringMaterials ScienceElectronic MaterialsSemiconductor DevicesSemiconductor MaterialsSemiconductor Device MaterialsSemiconductor HeterostructuresSemiconductor InterfacesSemiconductor PhysicsStrain EngineeringTwo-dimensional SemiconductorsAnnealingBarrier LayersContact ResistanceHeterostructuresTensile StrainThermal StabilityTwo-dimensional Electron GasesTwo-dimensional Heterostructures
Abstract In order to improve the thermal stability in AlGaN-channel two-dimensional electron gas (2DEG) heterostructures, we newly designed strain-controlled quaternary AlGaInN barrier layers, and then we grew them by metalorganic chemical vapor deposition. A 2DEG density as high as 2.5 × 10 13 cm −2 and a good surface morphology were obtained for an (Al 0.64 Ga 0.36 ) 0.976 In 0.024 N/Al 0.19 Ga 0.81 N heterostructure, in which in-plane tensile strain in the barrier layer was estimated to be 0.51%. It was also confirmed that the (Al 0.64 Ga 0.36 ) 0.976 In 0.024 N/Al 0.19 Ga 0.81 N heterostructure showed an excellent thermal stability in its 2DEG properties even at high temperatures up to 900 °C. As a result of their thermal stability improvement, we were also able to confirm that the contact resistance was improved by applying high-temperature annealing.
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