Hostname: page-component-cd9895bd7-lnqnp Total loading time: 0 Render date: 2024-12-28T20:12:13.131Z Has data issue: false hasContentIssue false

Two-dimensional imaging of the potential distribution within a core/shell nanowire by electron holography

Published online by Cambridge University Press:  01 May 2006

Jayhoon Chung
Affiliation:
Texas Materials Institute, University of Texas at Austin, Austin, Texas 78712
Lew Rabenberg*
Affiliation:
Texas Materials Institute, University of Texas at Austin, Austin, Texas 78712
*
a) Address all correspondence to this author. e-mail: lew.rabenberg@mail.utexas.edu
Get access

Abstract

Electrostatic potentials within a core/shell nanowire structure, composed of an intrinsic germanium core surrounded by its oxide and a heavily doped germanium shell, were investigated by electron holographic analysis on its cross-section. The potential distribution resulting from interface charges as well as dopants was successfully imaged. The surface potential, screening length, and doping concentration for the heavily doped germanium shell were determined quantitatively from the potential image. These characteristics were compared with values obtained from a numerical solution of Poisson's equation.

Type
Articles
Copyright
Copyright © Materials Research Society 2006

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1.Law, M., Goldberger, J., Yang, P.: Semiconductor nanowires and nanotubes. Ann. Rev. Mater. Res. 34, 83 (2004).Google Scholar
2.Lauhon, L.J., Gudiksen, M.S., and Lieber, C.M.: Semiconductor nanowire heterostructures. Philos. Trans. R. Soc. London, Ser. A, Math. Phys. Eng. Sci. 362, 1247 (2004).CrossRefGoogle ScholarPubMed
3.Berz, F. The surface space charge layer, in Surface Physics of Phosphors and Semiconductors edited by Scott, C.G. and Reed, C.E. (Academic Press, New York, 1975), p. 143.Google Scholar
4.Tabet, N., Faiz, M., Hamdan, N.M., Hussain, Z.: High resolution XPS study of oxide layers grown on Ge substrates. Surf. Sci. 523, 68 (2003).CrossRefGoogle Scholar
5.Hovis, J.S., Hamers, R.J., Greenlief, C.M.: Preparation of clean and atomically flat germanium(001) surfaces. Surf. Sci. 440, L815 (1999).CrossRefGoogle Scholar
6.Wang, D., Chang, Y., Wang, Q., Cao, J., Farmer, D.B., Gordon, R., Dai, H.: Surface chemistry and electrical properties of germanium nanowires. J. Am. Chem. Soc. 126, 11602 (2004).CrossRefGoogle ScholarPubMed
7.Midgley, P.A.: An introduction to off-axis electron holography. Micron 32, 167 (2001).CrossRefGoogle ScholarPubMed
8.Hanrath, T., Korgel, B.A.: Supercritical fluid-liquid-solid (SFLS) synthesis of Si and Ge nanowires seeded by colloidal metal nanocrystals. Adv. Mater. 15, 437 (2003).Google Scholar
9.Wang, Y.Y., Kawasaki, M., Bruley, J., Gribelyuk, M., Domenicucci, A., Gaudiello, J.: Off-axis electron holography with a dual-lens imaging system and its usefulness in 2-D potential mapping of semiconductor devices. Ultramicroscopy 101, 63 (2004).CrossRefGoogle ScholarPubMed
10.McCartney, M.R., ASU Holography (Arizona State University, Tempe, AZ, 2003) (unpublished software).Google Scholar
11.Ghiglia, D.C., Pritt, M.D.: Two-Dimensional Phase Unwrapping: Theory, Algorithms, and Software (Wiley, New York, 1998).Google Scholar
12.Wang, Z., Hirayama, T., Sasaki, K., Saka, H., Kato, N.: Electron holographic characterization of electrostatic potential distributions in a transistor sample fabricated by focused ion beam. Appl. Phys. Lett. 80, 246 (2002).CrossRefGoogle Scholar
13.Handler, P. Electrical properties of a clean germanium surface, in Semiconductor Surface Physics, edited by Kingston, R.H. (University of Pennsylvania Press, Philadelphia, PA, 1957), p. 23.CrossRefGoogle Scholar
14.Gajdardziska-Josifovska, M., Carim, A.H. Applications of electron holography, in Introduction to Electron Holography, edited by Völkl, E., Allard, L.F., and Joy, D.C. (Kluwer Academic, New York, 1999), p. 267.CrossRefGoogle Scholar
15.Chung, J., Rabenberg, L.: Mapping of electrostatic potentials within core-shell nanowires by electron holography. Appl. Phys. Lett. 88, 013106 (2006).CrossRefGoogle Scholar
16.Wang, Y.C., Chou, T.M., Libera, M., Kelly, T.F.: Transmission electron holography of silicon nanospheres with surface oxide layers. Appl. Phys. Lett. 70, 1296 (1997).CrossRefGoogle Scholar
17.Rau, W.D., Schwander, P., Braumann, F.H., Hoppner, W., Ourmazd, A.: Two-dimensional mapping of the electrostatic potential in transistors by electron holography. Phys. Rev. Lett. 82, 2614 (1999).CrossRefGoogle Scholar
18.Wang, Z., Kato, T., Shibata, N., Hirayama, T., Kato, N., Sasaki, K., Saka, H.: Characterizing an implanted Si/Si p -n junction with lower doping level by combined electron holography and focused-ion-beam milling. Appl. Phys. Lett. 81, 478 (2002).Google Scholar
19.Ko, K-S., Jung, W.C., Chung, J., Rabenberg, L. Damage caused by transverse scattering of gallium during FIB milling, in Proceedings of Microscopy and Microanalysis 2004 edited by And, I.M.erson, Price, R., Hall, E., Clark, E., and McKernan, S. (Cambridge University Press, New York, 2004), 1170CD.Google Scholar
20.Seiwatz, R., Green, M.: Space charge calculations for semiconductors. J. Appl. Phys. 29, 1034 (1958).CrossRefGoogle Scholar
21.Stern, F., Howard, W.E.: Properties of semiconductor surface inversion layers in the electric quantum limit. Phys. Rev. 163, 816 (1967).Google Scholar