Seminars Archive
The Interface Phase and the Schottky Barrier for a Crystalline Dielectric on Silicon
Abstract
Wednesday, July 7, 2004, 11:00
Seminar Room, ground floor, Building "T"
Sincrotrone Trieste, Basovizza
The Interface Phase and the Schottky Barrier for a
Crystalline Dielectric on Silicon
Marco Buongiorno Nardelli
( North Carolina State University and Oak Ridge National Laboratory,
USA)
Abstract
Exciting new classes of device applications are becoming viable because
of advances in ultra thin film growth of epitaxial oxides on
semiconductors. The central issue in the epitaxial oxide semiconductor
systems is the role of the interface. Preparation of the semiconductor
surface is essential to successful, high quality, crystalline oxide
formation. Furthermore, the chemical nature of the surface then
controls such fundamental properties of the system as band offsets,
band bending and transport. In this talk I will illustrate how
high-performance simulations combined with experiments have been able
to characterize an interface phase whose structure-specific chemical
bonding is fundamental in determining the properties of the semiconductor/crystalline
oxide system. This interface phase results
in gap states that cannot be readily identified with either of the
bulk terminations. Moreover, these interface states result in a
tunable Coulomb buffer whose properties can be modified to adjust the
offset of the relative electrostatic potential on either side of the
interface. I will illustrate this interface phase with the prototypical
case of silicide/oxide heteroepitaxy on silicon and
discuss the fundamental implications of this concept for science and
technology.