The movement of Cu in a HfO2-based resistive random access memory （RRAM） device is investigated in depth by first-principle calculations. Thermodynamics analysis shows that the dominant motion of Cu tends to be alon...The movement of Cu in a HfO2-based resistive random access memory （RRAM） device is investigated in depth by first-principle calculations. Thermodynamics analysis shows that the dominant motion of Cu tends to be along the [001] orientation with a faster speed. The migration barriers along different routes are compared and reveal that the [001] orientation is the optimal migration route of Cu in HfO2, which is more favorable for Cu transportation. Furthermore, the preferable HfOz growth orientation along [100], corresponding to Cu migration along [001], is also observed. Therefore, it is proposed that the HfO2 material should grow along [100] and the operating voltage should be applied along [001], which will contribute to the improvement of the response speed and the reduction of power consumption of RRAM.展开更多
Scaling analysis shows that if o（ε<sup>2</sup>, β<sub>1</sub>ε, γε） <sup>o</sup> （δ）, frontal geostrophic dynamics governs the behav-ior of an isolated bottom eddy in a fi...Scaling analysis shows that if o（ε<sup>2</sup>, β<sub>1</sub>ε, γε） <sup>o</sup> （δ）, frontal geostrophic dynamics governs the behav-ior of an isolated bottom eddy in a finite depth ambient fluid; and that the ambient flow induced bybottom eddy migration satisfies quasi-geostrophic dynamics. This two layer model includes the impor-tant processes of advection of bottom eddy due to ambient flow, baroclinic instability, and form dragintroduced by Rossby waves. The numerical results show that the three processes enhance theinstability and alter the migration speed of the bottom eddy, and that the form drag induces asignificant meridional drift of the eddy.展开更多
基金supported by the National Natural Science Foundation of China(No.61376106)
文摘The movement of Cu in a HfO2-based resistive random access memory （RRAM） device is investigated in depth by first-principle calculations. Thermodynamics analysis shows that the dominant motion of Cu tends to be along the [001] orientation with a faster speed. The migration barriers along different routes are compared and reveal that the [001] orientation is the optimal migration route of Cu in HfO2, which is more favorable for Cu transportation. Furthermore, the preferable HfOz growth orientation along [100], corresponding to Cu migration along [001], is also observed. Therefore, it is proposed that the HfO2 material should grow along [100] and the operating voltage should be applied along [001], which will contribute to the improvement of the response speed and the reduction of power consumption of RRAM.
基金This research was supported by NSFC(No.49276267)
文摘Scaling analysis shows that if o（ε<sup>2</sup>, β<sub>1</sub>ε, γε） <sup>o</sup> （δ）, frontal geostrophic dynamics governs the behav-ior of an isolated bottom eddy in a finite depth ambient fluid; and that the ambient flow induced bybottom eddy migration satisfies quasi-geostrophic dynamics. This two layer model includes the impor-tant processes of advection of bottom eddy due to ambient flow, baroclinic instability, and form dragintroduced by Rossby waves. The numerical results show that the three processes enhance theinstability and alter the migration speed of the bottom eddy, and that the form drag induces asignificant meridional drift of the eddy.
