Bloch States of the Interface Phase

Electrical conductance and capacitance measurements of metal oxide semiconductor devices have revealed the existence of Bloch states that are associated with the interface phase that is formed between commensurate Ba$_{.72}$Sr $_{.28}$O and Si(001). Conductance measurements of the interface states show loss peaks that can be modeled using a single relaxation time in contrast to the distribution of relaxation times required to reproduce conductance measurements of interface traps at the amorphous SiO$_{2}$ / Si interface. The measured magnitude, which is on the order of 4x10$^{13}$ eV$^{-1}$ cm$^{-2}$ and the character of the interface phase Bloch state (IPBS) density is consistent with local density approximation (LDA) calculations using a physical structure based on a one mono-atomic layer silicide. Research sponsored jointly by the Division of Materials Sciences and Engineering, Office of Basic Energy Sciences, U.S. Department of Energy at Oak Ridge National Laboratory under contract DE-AC05-00OR22725 with UT-Battelle, LLC and at the University of Tennessee under contract DE-FG02-01ER45937. Calculations have been performed on CCS supercomputers at Oak Ridge National Laboratory.