Hostname: page-component-cd9895bd7-dk4vv Total loading time: 0 Render date: 2024-12-27T01:55:50.508Z Has data issue: false hasContentIssue false

Ion-implantation Generated Nanovoids in Si and MgO Monitored by High Resolution Positron Beam Analysis

Published online by Cambridge University Press:  17 March 2011

S.W.H. Eijt
Affiliation:
Interfaculty Reactor Institute, Delft University of Technology, Mekelweg 15, NL-2629 JB Delft, The Netherlands
C.V. Falub
Affiliation:
Interfaculty Reactor Institute, Delft University of Technology, Mekelweg 15, NL-2629 JB Delft, The Netherlands
A. van Veen
Affiliation:
Interfaculty Reactor Institute, Delft University of Technology, Mekelweg 15, NL-2629 JB Delft, The Netherlands
H. Schut
Affiliation:
Interfaculty Reactor Institute, Delft University of Technology, Mekelweg 15, NL-2629 JB Delft, The Netherlands
P.E. Mijnarends
Affiliation:
Interfaculty Reactor Institute, Delft University of Technology, Mekelweg 15, NL-2629 JB Delft, The Netherlands
M.A. van Huis
Affiliation:
Interfaculty Reactor Institute, Delft University of Technology, Mekelweg 15, NL-2629 JB Delft, The Netherlands
A.V. Fedorov
Affiliation:
Interfaculty Reactor Institute, Delft University of Technology, Mekelweg 15, NL-2629 JB Delft, The Netherlands
Get access

Abstract

The formation of nanovoids in Si(100) and MgO(100) by 3He ion implantation has been studied. Contrary to Si in which the voids are generally almost spherical, in MgO nearly perfectly rectangular nanosize voids are created. Recently, the 2D-ACAR setup at the Delft Positron Research Center has been coupled to the intense reactor-based variable-energy positron beam POSH. This allows a new method of monitoring thin layers containing nanovoids or defects by depth-selective high-resolution positron beam analysis. The 2D-ACAR spectra of Si with a buried layer of nanocavities reveal the presence of two additional components, the first related to para-positronium (p-Ps) formation in the nanovoids, and a second one most likely related to unsaturated Si-bonds at the internal surface of the voids. The positronium is present in excited kinetic states with an average energy of 0.3 eV. Refilling of the cavities by means of low dose 3He implantation (1×1014 cm−2) followed by annealing reduces the formation of Ps and the width of the Ps peak in the ACAR spectrum. This width reduction is due to collisions of Ps with He atoms in the voids. In MgO, p-Ps formed with an initial energy of ~3 eV shows a final average energy of 1.6 eV at annihilation due to collisions with the cavity walls. Possibilities of this new, non-destructive method of monitoring the sizes of cavities and the evolution of nanovoid layers will be discussed.

Type
Research Article
Copyright
Copyright © Materials Research Society 2001

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

1. Positron beams and their applications, Coleman, P.G. (Ed.), (World Scientific, Singapore, 2000).Google Scholar
2. Peng, J.P., Lynn, K.G., Asoka-Kumar, P., Becker, D.P. and Hershman, D.R., Phys. Rev. Lett. 76, 2157 (1996).Google Scholar
3. Falub, C.V., Eijt, S.W.H., Veen, A. van, Mijnarends, P.E. and Schut, H., Proceedings ICPA-12, Munich, 2000 (in press).Google Scholar
4. Kooi, B.J., Veen, A. van, Hosson, J.Th.M. de, Schut, H., Fedorov, A.V. and Labohm, F., Appl. Phys. Lett. 76, 1110 (2000).Google Scholar
5. Eijt, S.W.H., Falub, C.V., Mijnarends, P.E. and Veen, A. van, Proceedings ICPA-12, Munich, 2000 (in press).Google Scholar
6. Schut, H., Veen, A. van, Labohm, F., Fedorov, A.V., Neeft, E.A.C. and Konings, R.J.M., Nucl. Instr. Meth. Phys. Res. B 147, 212 (1999).Google Scholar
7. Downing, R.G., Maki, J.T. and Fleming, R.F., J. Radioanal. Nucl. Chem. 112, 33 (1987).Google Scholar
8. Follstaedt, D.M., Myers, S.M., Petersen, G.A., and Medernach, J.W., J. Electron. Mater. 25, 151 (1996).Google Scholar
9. Veen, A. van, Schut, H., Vries, J. de, Hakvoort, R. A. and IJpma, M.R., in Positron Beams for Solids and Surfaces, edited by Schultz, P.J., Massoumi, G.R. and Simpson, P.J. (American Institute of Physics, New York, 1990), p. 171.Google Scholar
10. Nagashima, Y., Morinaka, Y., Kurihara, T., Nagai, Y., Hyodo, T., Shidara, T., and Nakahara, K., Phys. Rev. B 58, 12676 (1998).Google Scholar
11. Sferlazzo, P., Berko, S. and Canter, K.F., Phys. Rev. B 35, 5315 (1987).Google Scholar
12. Nagashima, Y. Kakimoto, M., Hyodo, T., Fujiwara, K., Ichimura, A., Chang, T., Deng, J., Akahane, T., Chiba, T., Suzuki, K., McKee, B.T.A. and Stewart, A.T., Phys. Rev. A 52, 258 (1995).Google Scholar
13. Nagashima, Y., Hyodo, T., Fujiwara, K. and Ichimura, A., J. Phys. B.: At. Mol. Opt. Phys. 31, 329 (1998).Google Scholar
14. He, Y.J., Hasegawa, M., Lee, R., Berko, S., Adler, D., Jung, A.-L., Phys. Rev. B 33, 5924 (1986).Google Scholar
15. Tang, Z., Hasegawa, M., Chiba, T., Saito, M., Kawasuso, A., Li, Z.Q., Fu, R.T., Akahane, T., Kawazoe, Y. and Yamaguchi, S., Phys. Rev. Lett. 78, 2236 (1997).Google Scholar
16. Biasini, A., Ferro, G., Monge, M.A., diFrancia, G. and Ferreira, V. La, J. Phys.: Condens. Matter 12, 5961 (2000).Google Scholar
17. Huang, C.C., Chang, I.M., Chen, Y.F. and Tseng, P.K., Physica B 245, 9 (1998).Google Scholar
18. Chen, D.M., PhD-thesis, City University of New York, 1987, Chapter 5.Google Scholar