Long Range Orderin Ultra-Thin SiO_2 Grown on Ordered Si(100)

摘要

In this paper, we investigate the correlation of electrical properties and structure of 1-4 nm thick SiO_2 grown on H-passivated Si(100) for ultra-thin gate applications. Ordered (1x1) Si(100) stable in ambient air is obtained at room temperature by wet chemical cleaning. Ion Beam Analysis using a combination of ion channeling and ~(16)O( alpha , alpha )~(16)O nuclear resonance yields Si areal densities lower than that of a bulkterminated Si crystal as calculated by Monte-Carlo simulations. This result indicates shadowing of Si substrate atoms by Si atoms in the thermally grown oxide. Detection of order by ion channeling is supported by Reflection High Energy Electron Diffraction (RHEED). C-V and I-V measurements are generally inconclusive for ultra-thin (1-2 nm) oxides because of leakage and breakdown. Surface charge analysis enables a comparison between ordered oxides and conventional oxides. The results are promising.