Japanese Journal of Applied Physics · 2012 · 10 citations · 26 references
EngineeringElectrical EngineeringMaterials ScienceMicroelectronicsSemiconductor DevicesSemiconductor MaterialsIii-v SemiconductorsSemiconductor Device MaterialsSemiconductor PhysicsWide Band Gap SemiconductorsWide-bandgap Semiconductor DevicesWide-bandgap SemiconductorsCurrent DensityGallium NitrideGallium Nitride (Gan) MaterialsGallium Nitride Power DevicesHigh-electron-mobility TransistorsTransconductanceWide Bandgap Semiconductor ApplicationsX-ray Diffraction Analysis
2.2-µm-thick crack-free GaN films were grown on patterned Si substrates. The crack-free GaN films were obtained by patterning Si substrate and optimizing the graded Al x Ga 1- x N layers. With the increase of the graded Al x Ga 1- x N layer thickness, the GaN crystal quality improved as judged from the X-ray diffraction data. By applying multi-Al x Ga 1- x N layers on the patterned Si substrate, a 31% reduction of tensile stress for the GaN film was obtained as measured by micro-Raman. For the AlGaN/GaN high electron mobility transistor grown on 1×1 cm 2 larger patterns, the device exhibits maximum drain current density of 776 mA/mm and maximum transconductance of 101 mS/mm.
26