Thermally propagated Al contacts on SiGe nanowires characterized by electron beam induced current in a scanning transmission electron microscope
- 29 October 2021
- journal article
- research article
- Published by IOP Publishing in Nanotechnology
- Vol. 33 (3), 035712
- https://doi.org/10.1088/1361-6528/ac2e73
Abstract
Here, we use electron beam induced current (EBIC) in a scanning transmission electron microscope to characterize the structure and electronic properties of Al/SiGe and Al/Si-rich/SiGe axial nanowire heterostructures fabricated by thermal propagation of Al in a SiGe nanowire. The two heterostructures behave as Schottky contacts with different barrier heights. From the sign of the beam induced current collected at the contacts, the intrinsic semiconductor doping is determined to be n-type. Furthermore, we find that the silicon-rich double interface presents a lower barrier height than the atomically sharp SiGe/Al interface. With an applied bias, the Si-rich region delays the propagation of the depletion region and presents a reduced free carrier diffusion length with respect to the SiGe nanowire. This behaviour could be explained by a higher residual doping in the Si-rich area. These results demonstrate that scanning transmission electron microscopy EBIC is a powerful method for mapping and quantifying electric fields in micrometer- and nanometer-scale devices.Keywords
Funding Information
- French Ministry of Research (“Recherches Technologiques de Base” Program)
This publication has 42 references indexed in Scilit:
- Back-to-back Schottky diodes: the generalization of the diode theory in analysis and extraction of electrical parameters of nanodevicesJournal of Physics: Condensed Matter, 2012
- Direct Determination of Minority Carrier Diffusion Lengths at Axial GaAs Nanowire p–n JunctionsNano Letters, 2012
- Mechanisms of Schottky Barrier Control on n-Type Germanium Using Ge3N4 InterlayersJournal of the Electrochemical Society, 2011
- Atomic Scale Alignment of Copper-Germanide Contacts for Ge Nanowire Metal Oxide Field Effect TransistorsNano Letters, 2009
- Coaxial silicon nanowires as solar cells and nanoelectronic power sourcesNature, 2007
- Low-voltage cross-sectional EBIC for characterisation of GaN-based light emitting devicesUltramicroscopy, 2007
- CASINO V2.42—A Fast and Easy‐to‐use Modeling Tool for Scanning Electron Microscopy and Microanalysis UsersScanning, 2007
- Silicidation of Silicon Nanowires by PlatinumNano Letters, 2007
- A specimen stage with no microscope modifications used to perform EBIC in a STEMJournal of Physics E: Scientific Instruments, 1988
- Charge collection scanning electron microscopyJournal of Applied Physics, 1982