| AVS 57th International Symposium & Exhibition | |
| Electronic Materials and Processing | Tuesday Sessions |
| Session EM-TuA |
| Session: | Defects in Semiconductors and Oxides |
| Presenter: | K.L. Kavanagh, Simon Fraser University, Canada |
| Authors: | K.L. Kavanagh, Simon Fraser University, Canada J. Salfi, University of Toronto, Canada I. Saveliev, University of Toronto, Canada D. Susac, Simon Fraser University, Canada M. Blumin, University of Toronto, Canada H. Ruda, University of Toronto, Canada |
| Correspondent: | Click to Email |
(001) directions. The InAs core radii varied from 10 to 60 nm, with GaAs shell thicknesses from 3 to 20 nm, depending on the growth time.
The ZB wires show a rectangular cross-section with <110> side facets while the WZ are hexagonal in cross-section. Strain relaxation via dislocations in individual wire is observed from the analysis of electron diffraction and Moire fringe patterns. Close to complete relaxation (95%) occurs preferentially in the longer radial <110> direction while a large residual strain of 30% to 50% is found along the wire length. Less strain relaxation in the perpendicular radial <110> direction is occurring consistent with a large radius of curvature in the wire morphologies.
The room temperature field effect mobility of unencapsulated InAs nanowires increases from approximately 1000 to several thousand as diameter increases from 30 to 80 nm, consistent with scattering from charged surface states or surface roughness. In comparison, InAs-GaAs core-shell nanowires have lower field effect mobility which does not increase with increasing diameter. A different, diameter-independent scattering mechanism related to strain relaxation limits the electronic mean-free-path in InAs-GaAs core-shell nanowires.