AVS 47th International Symposium
    Dielectrics Wednesday Sessions
       Session DI+EL+MS-WeA

Paper DI+EL+MS-WeA9
Microscopic Understanding of the Interface for the Heteroepitaxy of Crystalline Oxides on Silicon

Wednesday, October 4, 2000, 4:40 pm, Room 312

Session: Alternate Gate Dielectrics
Presenter: S. Gan, Pacific Northwest National Laboratory
Authors: S. Gan, Pacific Northwest National Laboratory
D.E. McCready, Pacific Northwest National Laboratory
D.J. Gaspar, Pacific Northwest National Laboratory
Y. Liang, Pacific Northwest National Laboratory
Correspondent: Click to Email
With SiO@sub 2@ approaching its fundamental limit as the gate dielectric in the existing Si-based CMOS technology, searching for alternative gate oxides with high dielectric constants is crucial for the next generation of devices. Recent work showed crystalline oxides such as SrTiO@sub 3@ (STO) is promising as an alternative to SiO@sub 2@ in MOS capacitors. One of the most important issues is how to integrate it into the existing Si-based technology, the first step of which is the growth of epitaxial oxides on Si substrates. Here we present our recent results on the study of the oxide-silicon interface, which plays a critical role in growing high-quality STO films. Employing scanning tunneling microscopy (STM), x-ray photoelectron spectroscopy (XPS), low-energy electron diffraction (LEED), we characterized the interfacial structure of each template layer (Sr and SrO) grown on Si in situ. The results revealed that the strontium covered silicon surfaces exhibit a series of reconstructions, including a (2x1) structure that provides the most stable interface for the growth of oxides. In addition, we used time-of-flight second ion mass spectrometry (TOF-SIMS) and x-ray diffraction (XRD) to investigate the interfacial chemistry and film structure. By combining these techniques, we correlated the interface structures with film properties, which allowed us to identify suitable interfacial templates for optimized growth. @FootnoteText@ Pacific Northwest Laboratory is a multiprogram national laboratory operated by Battelle Memorial Institute for the U.S. Department of Energy under Contract DE-AC06-76RLO 1830.