Aqueous ionic effect on electrochemical breakdown of Si-dielectric–electrolyte interface

Abstract

The breakdown of thin dielectric films (SiO2, Si3N4, HfO2) immersed in aqueous electrolyte was investigated. The current and the kinetics of dielectric breakdown caused by large cathodic electric field applied across the dielectric layer reveal the electrochemical nature of dielectric materials. Electrolytes play a huge role in the established dielectric-electrolyte interface with respect to the overall electrical behavior of the system. Although aqueous cations are considered as spectator ions in most electrochemical systems, in dielectric interfaces the current–potential characteristics depend on the type of cation. Computer simulation based on density functional theory and molecular dynamics showed cations affect the dielectric strength. The responses of various dielectric films to solution components provide invaluable information for dielectric-incorporated electrochemical systems.

Electrochemistry of the Silicon Oxide Dielectric Layer: Principles, Electrochemical Reactions, and Perspectives

“…As these models are based on a solid phase, the interfacing electrolyte solution should be reflected in the EOS system. As shown in Figure 2, the potential diagram of the silicon oxide was revisited with the effect of cationic species considered; thus, the potential of DB (V DB ) is driven predominantly by ion desolvation [16] . The electrical conduction pathway is rationalized using the percolation model, leading to thermal damage upon Joule heating during DB [15,34,35] .…”

“… The diagrams of the DB occurring at the silicon oxide dielectric layer. (a) The potential diagram along with the silicon oxide with or without the effect of cations [16] . (b) The percolation model [34] …”

“…This phenomenon has recently gained attention, and few studies regarding post‐DB damage in the EOS system have been reported [15,16] . A representative example is the work of Yun et al .…”

“…Iontronics, an emerging technology based on sophisticated control of ions as signal carriers that bridges solid‐state electronics and biological system, may guide such applications to totally enable ion‐based signal, ultimately mimicking neurological systems [94–96] . Moreover, DBs of silicon oxide in electrolyte solution have been previously demonstrated [15,16,97] …”

“…Consequently, it offers unprecedented opportunities for electrochemistry of the silicon oxide dielectric layer in the electrolyte‐oxide‐semiconductor (EOS) system. For example, the memristive behavior and conduction mechanism of silicon oxide have been of considerable interest in solid‐state electronics [14–18] . Even the formation of nanopores and further etching may be achieved at the silicon oxide [15,19] .…”