Abstract
A detailed core-level photoemission study of interfaces between thin alkali films andn-orp-type GaAs (110) formed at different substrate temperatures 85 K and 300 K) is reported. All the interfaces grown at 85 K (with Na, K, Rb, and Cs) were found to be non-reactive, while at 300 K, the interface with Na is reactive and that with Cs remains non-reactive. In case of the non-reactive interfaces, a strong band bending of ≊1.0 eV is observed forp-GaAs at alkali coverages as low as θ≊0.01 monolayers, but practically none forn-GaAs. This striking asymmetry in band bending is interpreted as a consequence of the donor character of the alkali atoms. On the other hand, an approximately symmetric band bending at low coverages is observed for the reactive interfaces of Na withn- andp-GaAs and assigned to defect states. For high alkali coverages (θ>2 monolayers), the final band bending is characterizeds by the same Fermilevel position forn- andp-GaAs, independent of the reactivity of the interface, and assigned to metal-induced gap states. Furthermore, systematic trends along the alkali series in Fermi-level position ionization energy, plasmon-loss features, and layer-dependent binding-energy shifts of alkali core levels are discussed.
Similar content being viewed by others
References
Brillson, L.J.: Surface Sci. Rep.2, 123 (1982)
Spicer, W.E., Chye, P.W., Skeath, P.R., Su, C.Y., Lindau, I.: J. Vac. Sci. Technol.16, 1422 (1979)
Lindau, I., Kendelewicz, T.: CRC Crit. Rev. Solid State Mater. Sci.13, 27 (1986)
Heine, V.: Phys. Rev.138, A 1689 (1965)
Louis, E., Yndurain, F., Flores F.: Phys. Rev. B13, 4408 (1976)
Cohen, M.L.: Adv. Electron. Electron Phys.51, 1 (1980)
Tersoff, J.: Phys. Rev. Lett.52, 465 (1984)
Flores, F., Tejedor, C.: J. Phys. C20, 145 (1987)
Prietsch, M., Domke, M., Laubschat, C., Kaindl, G.: Phys. Rev. Lett.60, 436 (1988)
Gregory, P.E., Spicer, W.E.: Phys. Rev. B12, 2370 (1975)
Clemens, H., Mönch, W.: CRC Crit. Rev. Solid State Sci.5, 273 (1975)
Mönch, W.: J. Vac. Sci. Technol. B6, 1270 (1988)
Prietsch, M., Laubschat, C., Domke, M., Kaindl, G.: Europhys. Lett.6, 451 (1988)
Kammerer, R., Barth, J., Gerken, F., Kungz, C., Flodstrøm, S.A., Johansson, L.I.: Phys. Rev. B26, 3491 (1981)
Eastman, D.E., Chiang, T.-C., Heimann, P., Himpsel, F.J.: Phys. Rev. Lett.15, 656 (1980)
Mönch, W.: Solid State Commun.58, 215 (1986)
Mönch, W., Bauer, R.S., Gant, H., Murshall, R.: J. Vac. Sci. Technol.21, 498 (1982)
Tang, J.Y.-F., Freeouf, J.L.: J. Vac. Sci. Technol. B2, 459 (1984)
Wolf, H.F.: Semiconductors. New York: Wiley 1971
Stiles, K., Kahn, A., Kilday, D.G., Margaritondo, G.: J. Vac. Sci. Technol. B5, 987 (1987)
Cao, R., Miyano, K., Kendelewicz, T., Chin, K.K., Lindau, I., Spicer, W.E.: J. Vac. Sci. Technol. B5, 998 (1987)
Troost, D., Koenders, L., Fan, L.-Y., Mönch, W.: J. Vac. Sci. Technol. B5, 119 (1987)
Cardona, M., Ley, L.: Photoemission in solids. Vol. 1. Berlin, Heidelberg, New York: Springer 1978
Kanski, J., Svensson, S.P., Andersson, T.G., LeLay, G.: Solid State Commun.60, 793 (1986)
Grant, R.W., Waldrop, J.R.: J. Vac. Sci. Technol. B5, 1015 (1987)
Derrien, J., Arnaud d'Avitaya, F.: Surface Sci.65, 668 (1977)
Stroscio, J.A., Feenstra, R.M.: Private communication (1988)
Prietsch, M., Laubschat, C., Domke, M., Kaindl, G.: Phys. Rev. B38, (1988, in press)
Domke, M., Mandel, T., Laubschat, C., Prietsch, M., Kaindl, G.: Surface Sci.189/190, 268 (1987)
Hohlfeld, A., Sunjic, M., Horn, K.: J. Vac. Sci. Technol. A5, 679 (1987)
Oelling, E.M., Miranda, R.: Surface Sci.177, L947 (1986)
Lang, N.D.: Phys. Rev. B4, 4234 (1971)
Serena, P.A., Garcia, N.: Surface Sci.189/190, 232 (1987)
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Prietsch, M., Domke, M., Laubschat, C. et al. Photoemission study of alkali/GaAs(110) interfaces. Z. Physik B - Condensed Matter 74, 21–33 (1989). https://doi.org/10.1007/BF01307236
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF01307236