Journal of Vacuum Science & Technology B Microelectronics and Nanometer Structures Processing Measurement and Phenomena · 1991 · 11 citations · 0 references
EngineeringElectrical EngineeringMaterials ScienceMicroelectronicsSemiconductor DevicesSemiconductor MaterialsQuantum ConfinementQuantum TunnelingQuantum WellsSemiconductor HeterostructuresSemiconductor PhysicsTunnelingCurrent-voltage CharacterizationCurrent-voltage RelationsCurrent-voltage RelationshipDifferential ResistanceResonant TunnelingResonant Tunneling DevicesTunneling In SemiconductorsTunneling Phenomena
We have observed singularities in current–voltage data that indicate charge quantization in the accumulation layer of resonant tunneling diodes with thick spacer layers. The electrons are strongly localized between the artificial barrier formed by the lightly doped emitter spacer layer and the first metallurgical barrier. Tunneling occurs between these states and those confined to the quantum well. We presume this process to be the source of negative differential resistance in the single- and double-well samples we have fabricated.