Evaluation of carrier density and mobility in Mn ion-implanted GaAs:Zn nanowires by Raman spectroscopyShow others and affiliations
2020 (English)In: Nanotechnology, ISSN 0957-4484, E-ISSN 1361-6528, Vol. 31, no 20, article id 205705Article in journal (Refereed) Published
Abstract [en]
The fabrication of complex nanoscale electronics with reduced dimensions poses challenges on novel techniques to accurately determine fundamental electronic parameters. In this article, we present a universal contactless method based on Raman scattering for measuring the mobility and hole concentration independently in GaAs:Zn and Mn ion-implanted GaAs:Zn nanowires, potentially of great interest for spintronics applications. Clear coupled longitudinal optical phonon-plasmon modes were recorded and fitted with a dielectric function, based on the Drude model, which includes contributions from both plasmons and phonons. From the fitting, we extract accurate values of the plasma frequency and plasma damping constant from which we directly calculate the hole density and mobility, respectively. The extracted mobilities were also used as input data for analysis of complementary four-probe transport measurements, where the corresponding hole concentrations could be calculated and found to be in good agreement with those extracted directly from the Raman data. We also investigated the influence of annealing of the GaAs:Zn nanowires on the hole concentration and mobility and found strong indications of thermally activated defects related to a formed crystalline As/oxide shell around the nanowires. The method proposed here is extremely powerful for the characterization of nanoelectronics in general, and nanospintronics in particular for which Hall measurements are difficult to pursue due to problems related to contact formation, as well as to inherent magnetic properties of the devices. © 2020 IOP Publishing Ltd.
Place, publisher, year, edition, pages
Bristol: Institute of Physics Publishing (IOPP), 2020. Vol. 31, no 20, article id 205705
Keywords [en]
Dilute magnetic semiconductors, Nanowires, Raman spectroscopy
National Category
Condensed Matter Physics
Identifiers
URN: urn:nbn:se:hh:diva-43225DOI: 10.1088/1361-6528/ab70faISI: 000537543400005PubMedID: 31995520Scopus ID: 2-s2.0-85082297722OAI: oai:DiVA.org:hh-43225DiVA, id: diva2:1475657
Note
Funding text: Sandeep Kumar and Chandni Devi acknowledge the support by Department of Science and Technology (DST) under Grant No: YSS/2015/001403 and University Grant Commission for project No. (F4-5(112-FRP)/2014(BSR)). The Brazilian authors acknowledge, for financial support, from the national agencies CNPq, CAPES and FINEP
2020-10-132020-10-132021-10-25Bibliographically approved