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Transport in High-Mobility Si1−xGex Heterostructures Grown by Molecular-Beam Epitaxy

Published online by Cambridge University Press:  25 February 2011

Don Monroe ,
Y.-H. Xie ,
E. A. Fitzgerald  and
P. J. Silverman
Don Monroe
Affiliation:
AT&T Bell Laboratories, P.O. Box 636, Murray Hill, NJ 07974
Y.-H. Xie
Affiliation:
AT&T Bell Laboratories, P.O. Box 636, Murray Hill, NJ 07974
E. A. Fitzgerald
Affiliation:
AT&T Bell Laboratories, P.O. Box 636, Murray Hill, NJ 07974
P. J. Silverman
Affiliation:
AT&T Bell Laboratories, P.O. Box 636, Murray Hill, NJ 07974
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Abstract

We report Hall mobilities (at T = 4.2K) as high as 180,000cm2V−1 s−1 in modulation-doped Si layers in Si1−x Gex heterostructures grown by Molecular-Beam Epitaxy. These mobilities reflect dramatic improvements in the quality of relaxed Si1−xGex buffer layers (with x'30%) grown by gradual grading of composition at high temperature. The resulting moderate threading dislocation densities (< 106 cm−2 ) appear to cause no mobility degradation. The strong damping of Shubnikov de Haas oscillations, as well as the increase of mobility with carrier density, indicate predominantly small-angle scattering. This suggests that residual Coulomb scattering from background impurities limit the mobility, rather than interface-roughness scattering as for the Si/SiO2 interface. The reduced interfacial scattering, as well as the strain-induced splitting of the valley degeneracy to select the two low-effective-mass valleys, significantly enhance room-temperature transport as well, with μHall ' 2,100cm2 V−1 s−1. We also observe a small splitting of the remaining twofold valley degeneracy using the integral quantized Hall effect. As a further indication of the high sample quality, measurements to 17T at 0.3K show indications of the v = 2/3 fractional quantum Hall effect.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 281: Symposium D – Semiconductor Heterostructures for Photonic and Electronic Applications , 1992 , 449
Copyright
Copyright © Materials Research Society 1993

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References

REFERENCES

1. Fitzgerald, E.A., Xie, Y.H., Green, M.L., Brasen, D., Kortan, A.R., Michel, J., Mii, Y.J., and Weir, B.E., Appl. Phys. Lett. 59, 811 (1991).Google Scholar
2. Fitzgerald, E.A., Xie, Y.H., Green, M.L., Brasen, D., Kortan, A.R., Mii, Y.J., Michel, J., Weir, B.E., Feldman, L.C., and Kuo, J.M., Mat. Res. Soc. Symp. Proc. 220, 211 (1991).Google Scholar
3. Tuppen, C.G., Gibbings, C.J., and Hockly, M., Mat. Res. Soc. Symp. Proc. 220, 187 (1991).Google Scholar
4. Xie, Y.-H., Fitzgerald, E.A., Mii, Y.J., Monroe, D., Thiel, F.A., Weir, B.E., and Feldman, L.C., Mat. Res. Soc. Symp. Proc. 220, 413 (1991).Google Scholar
5. Mii, Y.J., Xie, Y.H., Fitzgerald, E.A., Monroe, D., Thiel, F.A., Weir, B.E., Appl. Phys. Lett. 59, 1611 (1991).Google Scholar
6. Schäffler, F., Többen, D., Herzog, H.-J., Abstreiter, G., and Hollander, B., Semicond. Sci. Technol. 7, 260 (1992).Google Scholar
7. Fitzgerald, E.A., Xie, Y.-H., Monroe, D., Silverman, P.J., Kuo, J.M., Kortan, A.R., Thiel, F.A., and Weir, B.A., J. Vac. Sci. Technol. B 10, 1807 (1992).Google Scholar
8. Wang, P.J., Meyerson, B.S., Ismail, K., Fang, F.F., and Nocera, J. Mat. Res. Soc. Symp. Proc. 220, 403 (1991).Google Scholar
9. van de Walle, C.G. and Martin, R.M., Phys. Rev. B 34, 5621 (1986).Google Scholar
10. Gossman, H.-J., Schubert, E.F., Eaglesham, D.J., and Cerullo, M., Appl. Phys. Lett. 57, 2440 (1990).Google Scholar
11. Efros, A.L., Pikus, F.G., and Samsonidze, G.G., Phys. Rev. B 41, 8295 (1990).Google Scholar
12. Monroe, Don, unpublished.Google Scholar
13. Abstreiter, G., Brugger, H., Wolf, T., Jorke, H., and Herzog, H.J., Phys. Rev. Lett 30, 226 (1985).Google Scholar
14. see p. 571ff of Ando, T., Fowler, A.B., and Stern, F., Rev. Mod. Phys. 54, 437 (1982).Google Scholar
15. Nelson, S.F., Ismail, K., Nocera, J.J., Fang, F.F., Mendez, E.E., Chu, J.O., and Meyerson, B.S., Appl. Phys. Lett. 61, 64 (1992).Google Scholar
16. Stern, F. and Laux, S.E., Appl. Phys. Lett. 61, 1110 (1992).Google Scholar
17. Monroe, Don, Xie, Y.-H., Fitzgerald, E.A., and Silverman, P.J., Phys. Rev. B 46, 7935 (1992).Google Scholar