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The relations between the reset current IR, room temperature filament resistance R0, and third harmonic coefficient B0 were evaluated by a conical filament model. It was found that IR∼1/R0 when the filament is either very weak, where the filament is more conical, or quite strong, where the filament is more cylindrical. The physical implication of the B0 was also understood from the materials properties. The coherence between the model expectations for the bulkier conical filaments, typically found in TiO2, and the more random-network like filaments, typically found in NiO, suggests a common switching mechanism works in both materials. [ABSTRACT FROM AUTHOR]

This study examined the relationship between the conducting filament resistance and reset voltage during the resistance switching of TiO2 thin films assuming a filament with a conical shape. There was a critical resistance (∼20 Ω) of the set state above and below which the filament responded differently in response to the current. Maintaining a higher set state resistance was more beneficial in achieving a more uniform reset voltage. This filament model coincides well with the localized switching behavior and the recently microscopically observed filament shape. [ABSTRACT FROM AUTHOR]

The electrical conduction properties of 10-nm-thick atomic-layer deposited Al[sub 2]O[sub 3] thin films with Al bottom and Pt top electrodes were characterized for use in field emission display. The as-deposited films, grown at 300 °C, exhibited such a high electrical leakage that their electrical properties could not be measured. However, post-treatment at 300 °C under a remote O[sub 2] or H[sub 2]O plasma for 30 min improved the insulating properties of the Al[sub 2]O[sub 3] films. However, the electrical conduction mechanism, particularly in the high field (>4 MV/cm) was not Fowler–Nordheim (F–N) tunneling but was influenced by space charge limited conduction implying that there were many traps inside the dielectric film or the electrode interfaces. Postannealing of the top electrode at 300 °C in an oxygen atmosphere resulted in a F–N conduction mechanism by removing the interfacial traps. The calculated barrier height at the Al/Al[sub 2]O[sub 3] interface from the F–N fitting of the current density versus voltage curves using the electron effective mass (m[sup *]) of 0.5 m[sub 0] was approximately 2.0 eV. © 2002 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The film thickness-dependent imprinting behavior (voltage shift) of (Pb, La)(Zr, Ti)O[sub 3] capacitors was evaluated by a thermal stress process under a remanence bias. The remanent polarization (P[sub r]) was found to be almost independent of the film thickness whereas in the 50-300 nm range the relative dielectric constant (ε[sub r]) increased linearly with the square root of the film thickness. It was found that the voltage shift, which was attributed to the accumulation of charged defects near the electrode interface, also increased linearly with increasing film thickness. In addition, the charge accumulated thickness varied with the square root of the film thickness. This was established from a simple assumption that the level of charge accumulation is determined by the product of the total amount of charged defects (total film thicknessxcharged defect density) and the internal field that is generated by the P[sub r]. Therefore, the imprint is much more a bulk-related degradation phenomenon compared to the fatigue. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]