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We demonstrate the potential of using Si as n-type dopant in GaAs nanowires grown by molecular beam epitaxy. The amphoteric behavior of Si that typically accompanies the vapor-liquid-solid growth mode is adequately controlled when a shell doping scheme is utilized instead, i.e. when a Si-doped GaAs shell layer is grown conformally around the undoped GaAs nanowire core in the vapor-solid mode. The incorporation site of Si was evaluated by Raman spectroscopy, and correlated with the growth conditions of the doped shell. In that way, we identified a growth window that ensures the incorporation of Si as donor, and obtained donor concentrations up to 1 × 1019 cm-3, with the compensation level by Si acceptors remaining below 10%. Finally, resistivity measurements on planarized shell-doped nanowire ensembles were employed to probe the doping efficiency and the surface depletion of free-carriers. The achievement of n-type conductivity for nanowires is essential for the realization of functional devices, and is particularly significant when a dopant as well understood and advantageous as Si is employed.


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Shell-Doping of GaAs Nanowires with Si for n-Type Conductivity

Show Author's information Emmanouil Dimakis( )Manfred RamsteinerAbbes TahraouiHenning RiechertLutz Geelhaar
Paul-Drude-Institut für FestkörperelektronikHausvogteiplatz 5-710117BerlinGermany

Abstract

We demonstrate the potential of using Si as n-type dopant in GaAs nanowires grown by molecular beam epitaxy. The amphoteric behavior of Si that typically accompanies the vapor-liquid-solid growth mode is adequately controlled when a shell doping scheme is utilized instead, i.e. when a Si-doped GaAs shell layer is grown conformally around the undoped GaAs nanowire core in the vapor-solid mode. The incorporation site of Si was evaluated by Raman spectroscopy, and correlated with the growth conditions of the doped shell. In that way, we identified a growth window that ensures the incorporation of Si as donor, and obtained donor concentrations up to 1 × 1019 cm-3, with the compensation level by Si acceptors remaining below 10%. Finally, resistivity measurements on planarized shell-doped nanowire ensembles were employed to probe the doping efficiency and the surface depletion of free-carriers. The achievement of n-type conductivity for nanowires is essential for the realization of functional devices, and is particularly significant when a dopant as well understood and advantageous as Si is employed.

Keywords: core-shell, Raman spectroscopy, nanowires, molecular beam epitaxy, GaAs, Si doping

References(25)

1

Mårtensson, T.; Svensson, C. P. T.; Wacaser, B. A.; Larsson, M. W.; Seifert, W.; Deppert, K.; Gustafsson, A.; Wallenberg, L. R.; Samuelson, L. Epitaxial III-V nanowires on silicon. Nano Lett. 2004, 4, 1987-1990.

2

Bakkers, E. P. A. M.; Borgström, M. T.; Verheijen, M. A. Epitaxial growth of III-V nanowires on group IV substrates. MRS Bull. 2007, 32, 117-122.

3

Piccin, M.; Bais, G.; Grillo, V.; Jabeen, F.; De Franceschi, S.; Carlino, E.; Lazzarino, M.; Romanato, F.; Businaro, L.; Rubini, S.; Martelli, F.; Franciosi, A. Growth by molecular beam epitaxy and electrical characterization of GaAs nanowires. Physica E 2007, 37, 134-137.

4

Gutsche, C.; Lysov, A.; Regolin, I.; Blekker, K.; Prost, W.; Tegude, F. J. N-type doping of vapor-liquid-solid grown GaAs nanowires. Nanoscale Res. Lett. 2011, 6, 65.

5

Hilse, M.; Ramsteiner, M.; Breuer, S.; Geelhaar, L.; Riechert, H. Incorporation of the dopants Si and Be into GaAs nanowires. Appl. Phys. Lett. 2010, 96, 193104.

6

Dufouleur, J.; Colombo, C.; Garma, T.; Ketterer, B.; Uccelli, E.; Nicotra, M.; Fontcuberta i Morral, A. P-doping mechanisms in catalyst-free gallium arsenide nanowires. Nano Lett. 2010, 10, 1734-1740.

7

Ketterer, B.; Mikheev, E.; Uccelli, E.; Fontcuberta i Morral, A. Compensation mechanism in silicon-doped gallium arsenide nanowires. Appl. Phys. Lett. 2010, 97, 223103.

8

Schmidt, V.; Wittemann, J. V.; Senz, S.; Gösele, U. Silicon nanowires: A review on aspects of their growth and their electrical properties. Adv. Mater. 2009, 21, 2681-2702.

9

Bar-Sadan, M.; Barthel, J.; Shtrikman, H.; Houben, L. Direct imaging of single Au atoms within GaAs nanowires. Nano Lett. 2012, 12, 2352-2356.

10

Tambe, M. J.; Ren, S.; Gradecak, S. Effects of gold diffusion on n-type doping of GaAs nanowires. Nano Lett. 2010, 10, 4584-4589.

11

Breuer, S.; Pfüller, C.; Flissikowski, T.; Brandt, O.; Grahn, H. T.; Geelhaar, L.; Riechert, H. Suitability of Au- and self-assisted GaAs nanowires for optoelectronic applications. Nano Lett. 2011, 11, 1276-1279.

12

Tok, E. S.; Neave, J. H.; Ashwin, M. J.; Joyce, B. A.; Jones, T. S. Growth of Si-doped GaAs(110) thin films by molecular beam epitaxy; Si site occupation and the role of arsenic. J. Appl. Phys. 1998, 83, 4160-4167.

13

Ramsteiner, M.; Wagner, J.; Ennen, H.; Maier, M. Resonance Raman scattering of Si local vibrational modes in GaAs. Phys. Rev. B 1988, 38, 10669-10676.

14

Aspnes, D.; Studna, A. Dielectric functions and optical parameters of Si, Ge, GaP, GaAs, GaSb, InP, InAs, and InSb from 1.5 to 6.0 eV. Phys. Rev. B 1983, 27, 985-1009.

15

Chia, A. C. E.; LaPierre, R. R. Contact planarization of ensemble nanowires. Nanotechnology 2011, 22, 245304.

16

Heon Kim, Y.; Woo Park, D.; Jun Lee, S. Gallium-droplet behaviors of self-catalyzed GaAs nanowires: A transmission electron microscopy study. Appl. Phys. Lett. 2012, 100, 033117.

17

Tok, E. S.; Jones, T. S.; Neave, J. H.; Zhang, J.; Joyce, B. A. Is the arsenic incorporation kinetics important when growing GaAs(001), (110), and (111)A films? Appl. Phys. Lett. 1997, 71, 3278-3280.

18

López, M.; Nomura, Y. Surface diffusion length of Ga adatoms in molecular-beam epitaxy on GaAs(100)-(110) facet structures. J. Cryst. Growth 1995, 150, 68-72.

19

Rudolph, D.; Hertenberger, S.; Bolte, S.; Paosangthong, W.; Spirkoska, D.; Döblinger, M.; Bichler, M.; Finley, J. J.; Abstreiter, G.; Koblmüller, G. Direct observation of a noncatalytic growth regime for GaAs nanowires. Nano Lett. 2011, 11, 3848-3854.

20

Ambrosini, S.; Fanetti, M.; Grillo, V.; Franciosi, A.; Rubini, S. Vapor-liquid-solid and vapor-solid growth of self-catalyzed GaAs nanowires. AIP Advances 2011, 1, 042142.

21

Ashwin, M. J.; Newman, R. C.; Muraki, K. The infrared vibrational absorption spectrum of the Si-X defect present in heavily Si doped GaAs. J. Appl. Phys. 1997, 82, 137.

22

Wallentin, J.; Borgström, M. T. Doping of semiconductor nanowires. J. Mater. Res. 2011, 26, 2142-2156.

23

Colombo, C.; Heiß, M.; Grätzel, M.; Fontcuberta i Morral, A. Gallium arsenide p-i-n radial structures for photovoltaic applications. Appl. Phys. Lett. 2009, 94, 173108.

24

Northrup, J.; Zhang, S. Dopant and defect energetics: Si in GaAs. Phys. Rev. B 1993, 47, 6791-6794.

25

Neave, J. H.; Dobson, P. J.; Harris, J. J.; Dawson, P.; Joyce, B. A. Silicon doping of MBE-grown GaAs films. Appl. Phys. A 1983, 32, 195-200.

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Publication history
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Acknowledgements

Publication history

Received: 06 July 2012
Revised: 03 September 2012
Accepted: 29 September 2012
Published: 17 October 2012
Issue date: November 2012

Copyright

© Tsinghua University Press and Springer-Verlag Berlin Heidelberg 2012

Acknowledgements

Acknowledgements

The authors acknowledge Jacob Dinner for the fabrication of planarized NW ensembles as well as the realization of I-V and SEM measurements, and Claudia Herrmann for maintaining the MBE system.

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