First principles modeling of charged oxygen vacancy filaments in reduced TiO₂-implications to the operation of non-volatile memory devices

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• 作者：Liang Zhao^a ; Seong-Geon Park^b ; Blanka Magyari-Kö ; pe^a ; ^{blankamk@stanford.edu} ; Yoshio Nishi^a
• 关键词：Density functional theory ; TiO2 ReRAM ; Oxygen vacancy filament
• 刊名：Mathematical and Computer Modelling
• 出版年：2013
• 出版时间：July, 2013
• 年：2013
• 卷：58
• 期：1-2
• 页码：275-281
• 全文大小：1311 K

文摘

First principles density functional theory calculations were employed to study the band structure of reduced rutile TiO₂ and the implications of oxygen vacancy charge states on the switching mechanisms observed in resistance change random access memory devices. The formation of conductive paths in TiO₂ composed of oxygen vacancy filaments were investigated using the method to calculate the band-structure, electron localization functions, partial charge densities of defect states and the Bader charge decompositions. The thermodynamic stability of charged oxygen vacancies on resistive switching are discussed based on the defect formation energies and a resistive switching mechanism is proposed based on models of filament formation and rupture.