Recombination defects at the 4H-SiC/SiO2 interface investigated with electrically detected magnetic resonance and ab initio calculations

Abstract

The selectivity of electrically detected magnetic resonance (EDMR) is utilized to probe the dominant recombination defect at the Si-face 4H-SiC/SiO 2 interface. The nature of this defect has long been debated with the two main candidates being the Si vacancy (V Si) or the C-dangling bond (P bC). Through comparison between experimental EDMR measurements and ab initio calculations, an important performance limiting recombination defect observed with EDMR in the current generation of nMOSFETs is reasonably explained as a combination of the P bC and the dual-P bC defects. These defects match the symmetry, hyperfine interaction, and isotopic abundance observed in the experimental EDMR spectrum.

Two-dimensional defect mapping of the SiO2/4H−SiC interface

“…Here we interpret our results in the context of well-established interpretations, starting with the concept of dangling bonds at the oxide/semiconductor interface. As pointed out by various groups [12,33,34] and in accordance with the presented STEM analysis, incomplete crystal planes at the interface favor the generation of a disordered atomic region, giving rise to an increased density of dangling bonds at the interface. Contradicting explanations of the nature of these dangling bonds can be found in the literature, suggesting either carbon [33][34][35][36] or silicon dangling bonds [37][38][39].…”

“…As pointed out by various groups [12,33,34] and in accordance with the presented STEM analysis, incomplete crystal planes at the interface favor the generation of a disordered atomic region, giving rise to an increased density of dangling bonds at the interface. Contradicting explanations of the nature of these dangling bonds can be found in the literature, suggesting either carbon [33][34][35][36] or silicon dangling bonds [37][38][39]. Considering the large number of zero-phonon lines observed in low and room temperature PL for similar oxidation processes on 4H-C [40,41], correlated C dangling bonds with large varieties of possible geometries and backbone structures as proposed in Ref.…”

Modeling of Diffusion and Incorporation of Interstitial Oxygen Ions at the TiN/SiO2 Interface

“…Constructing a model of TiN GB/a-SiO 2 interface presents a significant challenge due to the disparity between the two surfaces and the absence of a connection scheme between O ions of the SiO 2 surface and Ti ions of TiN. Therefore, instead of using an epitaxial model of the type used in refs − , we explored different interface configurations using a finite cluster representation of TiN GB. If a free-standing cluster of sufficient size can capture the properties of the periodic system, this cluster can then be tessellated over the a-SiO 2 surface to allow a variety of connection schemes to be tested in an efficient manner.…”

Structural, elastic, vibrational and electronic properties of amorphous Sm2O3 from Ab Initio calculations

“…[52,53,54,55,56,57] These approaches have produced structures that have been used to successfully identify defect centers, breakdown mechanisms, and many more atomistic phenomena. [58,59,60] In the case of non-glass forming oxides greater care is needed when producing the amorphous structures via a melt-quench to ensure the structures produced represent the systems of interest. The difficulties arise as for these materials the amorphous structures only exist in thin films as the result of strain between oxide and substrate.…”