摘要

In modeling resistance switching of metal oxides, migration of ion species is assumed to explain the local modulation of energy barriers or microscopic changes of stoichiometry. This article addresses an additional aspect of ions migration, that is, space charge redistribution in metal oxides. Modeling charge migration and its impact on current-voltage (I-V) characteristics were evaluated based on a bi-layered switching material composed of a 'transport layer' and a 'tunnel layer'. A dipolar charge profile was assumed to describe a low resistance state, and it was found that the I-V slope of the negative differential resistance regime increases with the initially assumed dipolar space charge density. A similar behavior was demonstrated in experimental I-V characteristics, which were successfully reproduced by the developed model. Space charge redistribution in metal oxides provides additional insight towards obtaining a more complete understanding of resistance switching phenomena.

  • 出版日期2015-3

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