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Selective growth of B 1-NbN in Nb thin film by high-dose nitrogen molecular ion implantation

Published online by Cambridge University Press:  31 January 2011

Nobuo Tanabe  and
Masaya Iwaki
Nobuo Tanabe
Affiliation:
Fujikura Ltd., Kiba 1-5-1, Kohtoh-ku, Tokyo 135, Japan
Masaya Iwaki
Affiliation:
RIKEN (The Institute of Physical and Chemical Research), Hirosawa 2-1. Wako. Saitama-ken 351-01. Japan
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Abstract

Nitrogen molecular ion implantations have been performed in niobium thin films to form B 1-NbN layers with an accelerating voltage of 150 kV up to a dose of 5 × 1017 N2+ ions/cm2 at room temperature. Measurements of superconducting transition temperature (Tc), Auger electron spectroscopy analyses (AES), and x-ray diffraction analyses (XRD) have been carried out as a function of nitrogen dose in order to characterize the implanted layer. It has been found that there are two regions in the dose dependence of Tc; in the low-dose case, Tc decreases from the initial value of 8 K to less than 4.2 K with increasing dose, and in case of the high dose (more than 2.5 × 1017 ions/cm2) it increases rapidly to 11 K and becomes independent of the implantation dose. The XRD patterns indicate the generation of lattice disorder at the low dose, the formation of Nb2N and ∊NbN at the intermediate dose, and the formation of δNbN (B 1 structure) at the high dose; the selective growth of δNbN occurs at the highest dose, in spite of the fact that thermodynamically Nb2N and ∊NbN are equilibrium phases at room temperature and they are formed at the intermediate dose. In conclusion, high-dose nitrogen implantation at room temperature causes the formation of δNbN to increase Tc.

Type
Articles
Information
Journal of Materials Research , Volume 3 , Issue 6 , December 1988 , pp. 1227 - 1231
Copyright
Copyright © Materials Research Society 1988

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References

REFERENCES

1Mitsuoka, T., Yamashita, T., Nakazawa, T., Saitoh, Y., and Anayama, T., J. Appl. Phys. 39, 4788 (1968).CrossRefGoogle Scholar
2Bacon, D. D., English, A. T., Nakahara, S., Peters, F. G., Schreiber, H., and Dover, R. B. Van, J. Appl. Phys. 54, 6509 (1983).CrossRefGoogle Scholar
3Shinoki, F., Shoji, A., Kosaka, S., Takada, S., and Hayakawa, H., Appl. Phys. Lett. 38, 285 (1981).CrossRefGoogle Scholar
4Igarashi, M., Hikita, M., and Takei, K., Advances in Cryogenic Engineering (Plenum, New York, 1984), Vol. 30, p. 535.Google Scholar
5Iwaki, M., Application of Ion Beams in Materials Science, edited by Sebe, T. and Yamamoto, Y. (Housei U. P., Honsei, Japan, 1987), p. 95.Google Scholar
6Kelly, R., J. Vac. Sci. Technol. 21, 778 (1982).CrossRefGoogle Scholar
7Ohira, S. and Iwaki, M., Nucl. Instrum. Methods B 19/20, 162 (1987).CrossRefGoogle Scholar
8Linker, G., Smithey, R., and Meyer, O., J. Phys. F: Met. 14, L115 (1984).CrossRefGoogle Scholar
9Meyer, O., Mann, H., and Phrilingos, E., in Applications of Ion Beams to Metals, edited by Picraux, S. T., EerNisse, E. P., and Vook, F. L. (Plenum, New York, 1974), p. 15.CrossRefGoogle Scholar
10Crozat, P., Adde, R., Chaumont, J., Bernas, H., and Zenatti, D., in Ref. 9, p. 27.Google Scholar
11Linker, G., Radiat. Effects 47, 225 (1980).CrossRefGoogle Scholar
12Gamo, K., Goshi, H., Takai, M., Iwaki, M., Masuda, K., and Namba, S., Jpn, J. Appl. Phys. 10, 1853 (1977).CrossRefGoogle Scholar
13Tanda, S., Sakazume, K., Sano, S., Ohta, H., and Iwaki, M., Proceedings of the 9th Symposium on Ion Sources and Ion-Assisted Technology (The Research Group of Ion Engineering in Ion Beam Engineering Experimental Laboratory, Kyoto University, Kyoto, Japan, 1985), p. 495.Google Scholar
14Manning, I. and Mueller, G. P., Comput. Phys. Commun. 7, 85 (1974).CrossRefGoogle Scholar
15Youngblood, G., Myhra, S., and Deford, J., Phys. Rev. 188, 1101 (1969).CrossRefGoogle Scholar
16Elliot, R. P., Constitution of Binary Alloys (McGraw-Hill, New York, 1965), 1st Suppl., p. 261.Google Scholar