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Transport Properties of Polycrystalline SiGe Thin Films Grown on SiO2

Published online by Cambridge University Press:  26 February 2011

Minoru Mitsui
Affiliation:
Center for Crystal Science and Technology, University of Yamanashi, Miyamae-Cho, Kofu 400–8511, Japan.
Keisuke Arimoto
Affiliation:
Center for Crystal Science and Technology, University of Yamanashi, Miyamae-Cho, Kofu 400–8511, Japan.
Junji Yamanaka
Affiliation:
Center for Crystal Science and Technology, University of Yamanashi, Miyamae-Cho, Kofu 400–8511, Japan.
Kiyokazu Nakagawa
Affiliation:
Center for Crystal Science and Technology, University of Yamanashi, Miyamae-Cho, Kofu 400–8511, Japan.
Kentarou Sawano
Affiliation:
The University of Tokyo, Tokyo 113–8656, Japan.
Yasuhiro Shiraki
Affiliation:
Musashi Institute of Technology, Tokyo 158–8557, Japan.
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Abstract

Transport properties of polycrystalline Si1−xGex (x = 0, 30, 50 and 70) thin films on SiO2 were studied by Hall measurements and transport properties of the TFTs fabricated on the films were characterized. Si1−xGex films were p-type in spite of non-doping. Room temperature hole densities of Si1−xGex films increased from 5 × 1013 to 5 × 1016 cm−3 as Ge concentration increased from 30 % to 70 %. The acceptor levels in Si1−xGex were located at 0.43, 0.40 and 0.34 eV for x=0.3, 0.5 and 0.7 from valence band, respectively. The high leakage current of SiGe-TFTs was observed and drain current could not be turned off even when the high gate voltage was applied. The acceptor density increased with increasing annealing temperature from 700 °C to 800 °C. The leakage currents were independent of the annealing temperature and is thought to originate from Ge-related defects in grain boundaries.

Type
Research Article
Copyright
Copyright © Materials Research Society 2005

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References

REFERENCES

1. Hwang, C. W., Ryu, M. K., Kim, K. B., Lee, S. C. and Kim, C. S., J. Appl. Phys. 77, 3042 (1995).Google Scholar
2. Olivares, J., Rodriguez, A., Sangrador, J., Rodriguez, T., Ballesteros, C. and Kling, A., Thin Solid Films 337, 51 (1999).Google Scholar
3. Yamaguchi, S., Park, S. K., Sugii, N., Nakagawa, K. and Miyao, M., Thin Solid Films 369, 195 (2000).Google Scholar
4. King, T. J. and Saraswat, K. C., IEEE Trans. Electron Devices 41, 1581 (1994).Google Scholar
5. Tsai, J. A., Tang, A. J., Noguchi, T. and Reif, R., J. Electrochem. Soc. 142, 3220 (1995).Google Scholar
6. Kim, J. W., Ryu, M. K., Kim, K. B., Hwang, C. W., Bae, B. S., Han, M. K. and Kim, S. J., Jpn. J. Appl. Phys. 35, L757 (1996).Google Scholar
7. Seto, J. Y. W., J. Appl. Phys. 46, 5247 (1975).Google Scholar