Limitations in the methods of determination of conduction mechanisms in high-permittivity dielectric nano-layers

• Published in: Physica. B, Condensed matter Vol. 398; no. 1; pp. 28 - 32
• Main Author: Novkovski, N.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.08.2007; Elsevier
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Determination of conduction mechanisms; Electronic structure and electrical properties of surfaces, interfaces, thin films and low-dimensional structures; Electronic transport in multilayers, nanoscale materials and structures; Exact sciences and technology; Leakage current analysis; Physics; Ultrathin interfacial layers; 73.61.−r; 77.55.+f; 73.40.Qv; Leakage current analysis; Determination of conduction mechanisms; Ultrathin interfacial layers; Interfacial layer; Electrical conductivity; Stacking sequence; Roughness; Tantalum oxides; Determination of conduction mechanisms; Leakage current analysis; Ultrathin interfacial layers; Nanostructures; Leakage currents; Poole-Frenkel effect; 73.40.Qv; 73.61.-r; 77.55.+f; Silicon oxides; High k dielectric; IV characteristic
• ISSN: 0921-4526; 1873-2135
• DOI: 10.1016/j.physb.2007.04.012

The standard methods of determination of the dominant conduction mechanisms in high-permittivity dielectrics were discussed for the case of very thin films. The outcomes from the estimation method were tested on the theoretical results obtained by the use of a comprehensive model describing the I– V characteristics of Ta 2O 5/SiO 2 stacked layers. It is shown that the standard method based on the determination of a slope in Poole–Frenkel plot provides only a rough estimation that may lead in some cases to essentially incorrect results. The observed disagreement is explained by the modifications induced by the presence of an unavoidably grown SiO 2-like few nanometers thick interfacial layer.