Demonstration of Confined Electron Gas and Steep-Slope Behavior in Delta-Doped GaAs-AlGaAs Core–Shell Nanowire Transistors

• DOI: 10.1021/acs.nanolett.5b00518
• Publication Date: 2015-04-29T17:47:24Z
• Authors: S. Morkötter; N. Jeon; D. Rudolph; B. Loitsch; D. Spirkoska; E. Hoffmann; M. Döblinger; S. Matich; J. J. Finley; L. J. Lauhon; G. Abstreiter; G. Koblmüller
• Keywords: Electron Mobility

Strong surface and impurity scattering in III–V semiconductor-based nanowires (NW) degrade the performance of electronic devices, requiring refined concepts for controlling charge carrier conductivity. Here, we demonstrate remote Si delta (δ)-doping radial GaAs-AlGaAs core–shell NWs that unambiguously exhibit a strongly confined electron gas with enhanced low-temperature field-effect mobilities up to 5 × 103 cm2 V–1 s–1. The spatial separation between high-mobility free at NW interface dopants shell is directly verified by atom probe tomographic (APT) analysis, band-profile calculations, transport characterization advanced transistor (FET) geometries, demonstrating powerful control over density Multigated NW-FETs allow us spatially resolve channel width- crystal phase-dependent variations mobility along single NW-FETs. Notably, dc output transfer characteristics these n-type depletion mode reveal excellent drain current saturation record low subthreshold slopes 70 mV/dec on/off ratios >104–105 room temperature.