Stability and electronic properties of silicates in the system SiO₂–Pr₂O₃–Si(001)

Abstract

Pr2O3 is one of the most promising hetero-oxides that are the candidates of choice to replace SiO2 as the gate dielectric material for sub-0.1 µm CMOS technology. In order to enable process integration, however, hetero-oxides require substantial characterization. In particular, the basic interaction mechanisms at the interface to the silicon substrate are the key issues. A solid knowledge of these mechanisms is required to address reliability arguments. The challenges in material science are to understand the chemical bonding of the hetero-oxides and Si on a microscopic scale. We report on the specific variations in the electronic structure which are evident in the valence band features around resonant excitation at the Pr 4d threshold. We also determine the valance band discontinuities at the Pr2O3/Si(001) interface and follow the changes in the surface potentials to develop a band scheme, a prerequisite to understanding the properties of charge transport across that interface.

Al-Oxynitride Buffer Layer Facilities for PrOX/SiC Interfaces

“…Depending on the preparation conditions and methods, the reported energy gaps of PrO X films are quite different (2-5.5 eV), but mostly smaller than that of other high-k candidates like hafnium oxide (HfO 2 ) [9,10]. But even for HfO 2 small conduction band offset values have been reported recently [11] and the need of a buffer layer was postulated.…”