Dangling bond defects at Si-SiO2 interfaces: Atomic structure of the P-b1 center

Roberto Car, Alfredo Pasquarello
2000
Journal paper

Abstract

Using a first-principles approach, we characterize dangling bond defects at Si-SiO2 interfaces by calculating hyperfine parameters for several relaxed structures; Interface models, in which defect Si atoms remain close to crystalline sites of the substrate upon relaxation, successfully describe P-b and P-b0 defects at (111) and (100) interfaces, respectively. On the basis of calculated hyperfine parameters, we discard models of the P-b1 defect containing a first neighbor shell with an O atom or a strained bond. A novel model consisting of an asymmetrically oxidized dimer yields hyperfine parameters in excellent agreement with experiment and is proposed as the structure of the P-b1 center.

Official source

https://infoscience.epfl.ch/record/141679?ln=en

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