S. Fung

Conduction mechanisms at low- and high-resistance states in aluminum/anodic aluminum oxide/aluminum thin film structure

In this work, conduction mechanisms of Al/anodic Al oxide/ Al structure, which exhibits resistive switching behavior, have been investigated. The low-resistance state shows ohmic conduction with a metal-like behavior similar to that of pure aluminum. The situation can be explained by the existence of the metallic filament formed by the excess Al in the Al oxide. On the other hand, the high-resistance state (HRS) shows two distinct regimes: ohmic conduction at low fields with a semiconductor-like behavior; and a non-ohmic conduction at high fields. The ohmic conduction of HRS at low fields is attributed to the electron hopping between the states in the oxide with the activation energy of ∼0.23u2009eV. It is suggested that the conduction of HRS at high fields (the maximum voltage is lower than the set voltage) is due to the field-enhanced thermal excitation of the electrons trapped in the states of the metallic Al nano-phase into the conduction band of the Al oxide or the electron emission from the potential we...

Post-growth annealing induced change of conductivity in As-doped ZnO grown by radio frequency magnetron sputtering

conductivity was consistent with the AsZn(VZn)2 shallow acceptor model. Further increasing the annealing temperature would decrease the hole concentration of the samples finally converted the sample back to n-type. With evidence, it was suggested that the removal of the p-type conductivity was due to the dissociation of the AsZn(VZn)2 acceptor and the creation of the deep level defect giving rise to the green luminescence. V C 2011 American Institute of Physics.

Flexible Write-Once–Read-Many-Times Memory Device Based on a Nickel Oxide Thin Film

A write-once-read-many-times (WORM) memory device based on conduction switching of a NiO thin film in a metal-insulator-metal structure is fabricated on a flexible substrate. The device can be switched from a low-conductance state (unprogrammed state) to a high-conductance state (programmed state) with the formation of conductive filament(s) in the NiO layer. The two memory states can be easily distinguished at a very low reading voltage. For example, at the reading voltage of 0.1 V, the current ratio of the state programmed at 3 V for 1 μs to the unprogrammed state is larger than 104. The WORM device exhibits good reading-endurance and data-retention characteristics. The flexible device is promising for low-cost and low-power archival storage applications.

Resistive Switching Behavior of Partially Anodized Aluminum Thin Film at Elevated Temperatures

Resistive switching behavior of partially anodized aluminum thin film has been investigated at temperatures of 25 <formula formulatype=inline><tex Notation=TeX>

A quantitative modeling of the contributions of localized surface plasmon resonance and interband transitions to absorbance of gold nanoparticles

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Deep level transient spectroscopic study of oxygen implanted melt grown ZnO single crystal

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Effect of Heat Diffusion During State Transitions in Resistive Switching Memory Device Based on Nickel-Rich Nickel Oxide Film

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Positron annihilation study of defects in electron-irradiated single crystal zinc oxide

</tex></formula>. Both the reset and set voltages decrease with increasing temperature, showing Arrhenius-like dependence with small activation energies. The pulse voltage experiment also suggests that the conductive filament breaking/reconnection is easier to occur at a higher temperature. Some possible mechanisms for the phenomena are discussed. On the other hand, at elevated temperatures without continuous electric field applied, while the high-resistance state exhibits no significant change with time, the low-resistance state (LRS) shows a continuous degradation, and there is a sudden failure. The LRS failure time shows Arrhenius dependence with an activation energy of <formula formulatype=inline><tex Notation=TeX>

Monte carlo simulation of positron induced secondary electrons in thin carbon foils

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A driven diffusion equation approach for optimization of a digital spectrum stabilizer

</tex></formula>1.3 eV, suggesting that the LRS failure could be due to the migration of the excess Al atoms at high temperatures.