Impact of local structural and electrical properties of grain boundaries in polycrystalline HfO2 on reliability of SiOx interfacial layer

Abstract Using nanometer-resolution characterization techniques, we present a study of the local structural and electrical properties of grain boundaries (GBs) in polycrystalline high-κ (HK) dielectric and their role on the reliability of underlying interfacial layer (IL). A detailed understanding of this analysis requires characterization of HK/IL dielectrics with nanometer scale resolution. In this work, we present the impact of surface roughness, thickness and GBs containing high density of defects, in polycrystalline HfO 2 dielectric on the performance of underlying SiO x ( x  ⩽ 2) IL using atomic force microscopy and simulation (device and statistical) results. Our results show SiO x IL beneath the GBs and thinner HfO 2 dielectric experiences enhanced electric field and is likely to trigger the breakdown of the SiO x IL.

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