TY - JOUR

T1 - Surface morphology of epitaxial lattice-matched Ba0.7Sr0.3O on Si(0 0 1) and vicinal Si(0 0 1)-4°[1 1 0] substrates

AU - Zachariae, J.

AU - Pfnür, Herbert

N1 - Funding information: We thank especially Dr. Wormeester, University of Twente, for software support (WinSpa32). Helpful discussions with Prof. Wollschläger and Dr. Tegenkamp and a critical reading of the manuscript by Prof. Wollschläger are gratefully acknowledged. This work was supported by the Deutsche Forschungsgemeinschaft (Grant No. Pf238/18).

PY - 2006/5/22

Y1 - 2006/5/22

N2 - Exploring ways for self-organized structuring of insulating thin films, we investigated the possibility to produce replicas of step trains, given by a vicinal Si(0 0 1)-4°[1 1 0] surface, in layers of crystalline and perfectly lattice-matched Ba0.7Sr0.3O. For this purpose, we carried out high-resolution spot profile analyses in low-energy electron diffraction (SPA-LEED) both on flat Si(0 0 1) and on Si(0 0 1)-4°[1 1 0]. Oxide layers were generated by evaporating the metals in oxygen ambient pressure with the sample at room temperature. Our G(S) analysis of these mixed oxide layers reveals a strong influence of local compositional fluctuations of Sr and Ba ions and their respective scattering phases, which appears as an unphysically large variation of layer distances. Nevertheless, we are able to show that quite smooth and closed oxide films are obtained with an rms roughness of about 1 ML. These Ba0.7Sr0.3O films directly follow the step train of Sr-modified vicinal Si surfaces that form (1 1 3) oriented facets after adsorption of a monolayer of Sr. This proves that self-organized structuring of insulating films can indeed be an effective method.

AB - Exploring ways for self-organized structuring of insulating thin films, we investigated the possibility to produce replicas of step trains, given by a vicinal Si(0 0 1)-4°[1 1 0] surface, in layers of crystalline and perfectly lattice-matched Ba0.7Sr0.3O. For this purpose, we carried out high-resolution spot profile analyses in low-energy electron diffraction (SPA-LEED) both on flat Si(0 0 1) and on Si(0 0 1)-4°[1 1 0]. Oxide layers were generated by evaporating the metals in oxygen ambient pressure with the sample at room temperature. Our G(S) analysis of these mixed oxide layers reveals a strong influence of local compositional fluctuations of Sr and Ba ions and their respective scattering phases, which appears as an unphysically large variation of layer distances. Nevertheless, we are able to show that quite smooth and closed oxide films are obtained with an rms roughness of about 1 ML. These Ba0.7Sr0.3O films directly follow the step train of Sr-modified vicinal Si surfaces that form (1 1 3) oriented facets after adsorption of a monolayer of Sr. This proves that self-organized structuring of insulating films can indeed be an effective method.

KW - Growth

KW - Insulating surfaces

KW - LEED

KW - Oxides

KW - Photoelectron spectroscopy

UR - http://www.scopus.com/inward/record.url?scp=33746940343&partnerID=8YFLogxK

U2 - 10.1016/j.susc.2006.05.002

DO - 10.1016/j.susc.2006.05.002

M3 - Article

AN - SCOPUS:33746940343

VL - 600

SP - 2785

EP - 2794

JO - Surface Science

JF - Surface Science

SN - 0039-6028

IS - 13

ER -