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Title: Oxygen vacancy defects in Ta{sub 2}O{sub 5} showing long-range atomic re-arrangements

The structure, formation energy, and energy levels of the various oxygen vacancies in Ta{sub 2}O{sub 5} have been calculated using the λ phase model. The intra-layer vacancies give rise to unusual, long-range bonding rearrangements, which are different for each defect charge state. The 2-fold coordinated intra-layer vacancy is the lowest cost vacancy and forms a deep level 1.5 eV below the conduction band edge. The 3-fold intra-layer vacancy and the 2-fold inter-layer vacancy are higher cost defects, and form shallower levels. The unusual bonding rearrangements lead to low oxygen migration barriers, which are useful for resistive random access memory applications.
Authors:
;  [1]
  1. Engineering Department, Cambridge University, Cambridge CB2 1PZ (United Kingdom)
Publication Date:
OSTI Identifier:
22257814
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 104; Journal Issue: 11; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; BONDING; FORMATION HEAT; OXYGEN; TANTALUM OXIDES; VACANCIES