@misc{10481/112381,
year = {2026},
month = {3},
url = {https://hdl.handle.net/10481/112381},
abstract = {We systematically investigated TiN/Ti/HfO2/W memristive architectures by varying the HfO2 and the Ti layer thickness ratios to optimize memory window characteristics and switching stability. Devices with balanced thickness configurations between the Ti and the HfO2 layers achieved optimal performance with memory windows exceeding two orders of magnitude and superior cycle-to-cycle stability. Kinetic Monte Carlo simulations revealed that optimal memory window performance correlates directly with controlled oxygen vacancy-ion dynamics during forming, set, and reset processes by the thickness of both layers. A Ti/HfO2 thickness ratio close to one provides an optimal balance between oxygen ion generation in the HfO2 layer and ion storage in the Ti reservoir, which spontaneously becomes TiOx previously. When the TiOx layer is relatively thin, compared to the HfO2 layer, a large number of oxygen ions are confined near the HfO2/TiOx interface. As a consequence, during the reset process, a large number of oxygen ions can recombine simultaneously with oxygen vacancies, significantly increasing cycle-to-cycle variability. On the contrary, a thicker Ti layer allows oxygen ions to migrate excessively far from the interface, reducing the effective recombination rate during the reset process. These dynamics also depend on the number of oxygen ions available, which is correlated to the HfO2 layer thickness. This balance explains the superior stability and enhanced memory window observed in devices with near-unity thickness ratios. Our findings establish quantitative design principles for bilayer oxide memristors, demonstrating that thickness ratio optimization enables precise control over memory window characteristics and switching stability for practical memory applications.},
publisher = {Elsevier},
keywords = {Memristors},
keywords = {Resistive memory},
keywords = {kinetic Monte Carlo simulation},
title = {Thickness-dependent resistive switching in engineered TiN/Ti/HfO2/W memristors},
doi = {10.1016/j.micrna.2026.208658},
author = {López, A. and González, M.B. and Cantudo, A. and Saludes Tapia, M. and Ríos, P and Jiménez Molinos, F. and Roldán, J.B. and Villena, M.A.},
}