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C. Först, C. Ashman, K. Schwarz, P. Blöchl:
"Growth of high-K Oxides on Silicon: SrTiO₃/Si(001)";
Poster: Application of Density-Functional Theory in Condensed-Matter Physics, Surface Physics,Chemistry, Engineering, and Biology, Berlin, Germany; 21.07.2003 - 30.07.2003.

Scaling of semiconductor devices currently results in structures with nearly atomic dimensions. Gate oxides, which separate the switching current from the drive current in a MOSFET transistor, are approaching a thickness range of only few atomic layers, so that quantum-mechanical leakage currents become intolerable. New insulating materials with larger dielectric constants, i.e. high-k oxides, can be implemented at a larger physical thickness with electrical properties equivalent to those of an ultra-thin conventional SiO2 gate oxide. State-of-the-art electronic structure calculations and ab-initio molecular dynamics simulations have been performed to investigate the growth of SrTiO3, one of the most promising high-k oxide, on Si(001). The understanding of Sr adsorption leads to an electronically saturated template for oxide growth. I will present the atomic and electronic structure of the SrTiO3/Si(001) interface. The structural changes upon variation of the oxygen partial pressure have been investigated. Based on these results, a method to engineer the band offsets in order to obtain an acceptable injection barrier will be proposed.