Journal of Computational Electronics

, Volume 11, Issue 3, pp 272–279 | Cite as

Doping of SiGe core-shell nanowires

  • Michele Amato
  • Riccardo Rurali
  • Stefano Ossicini


Dopant deactivation in pure Si and pure Ge nanowires (NWs) can compromise the efficiency of the doping process at nanoscale. Quantum confinement, surface segregation and dielectric mismatch, in different ways, strongly reduce the carrier generation induced by intentional addition of dopants. This issue seems to be critical for the fabrication of high-quality electrical devices for various future applications, such as photovoltaics and nanoelectronics. By means of Density Functional Theory simulations, we show how this limit can be rode out in core-shell silicon-germanium NWs (SiGe NWs), playing on the particular energy band alignment that comes out at the Si/Ge interface. We demonstrate how, by choosing the appropriate doping configurations, it is possible to obtain a 1-D electron or hole gas, which has not to be thermally activated and which can furnish carriers also at very low temperatures. Our findings suggest core-shell NWs as possible building blocks for high-speed electronic device and new generation solar cells.


Core-shell NWs Doping Electron and hole gas Photovoltaics DFT 



M. Amato and S. Ossicini greatly acknowledge the Transnational Access Programme of the HPC-EUROPA2 Project and the European Community’s Seventh Framework Programme (FP7/2007-2013) under Grant Agreement 245977, Ministero Affari Esteri, Direzione Generale per la Promozione and Cooperazione Culturale. Funding under Contract Nos. TEC2009-06986, FIS2009-12721-C04-03, and CSD2007-00041 are greatly acknowledged. The authors thankfully acknowledge the computer resources, technical expertise and assistance provided by the Res Española de Supercomputaciòn and the CINECA award under the ISCRA initiative (No. HP10BQNB3U), for the availability of high performance computing resources and support.


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Copyright information

© Springer Science+Business Media LLC 2012

Authors and Affiliations

  • Michele Amato
    • 1
    • 2
  • Riccardo Rurali
    • 3
  • Stefano Ossicini
    • 1
    • 2
    • 4
  1. 1.Dipartimento di Scienze e Metodi dell’IngegneriaUniversità di Modena e Reggio EmiliaReggio EmiliaItaly
  2. 2.“Centro S³”CNR-Istituto NanoscienzeModenaItaly
  3. 3.Institut de Ciència de Materials de Barcelona (ICMAB–CSIC)Bellaterra, BarcelonaSpain
  4. 4.Centro Interdipartimentale “En&Tech”Università di Modena e Reggio EmiliaReggio EmiliaItaly

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