Resistive switching characteristic of Ce_0.9Y_0.1O₂/TiO₂ bi-layer structure by photochemical metal-organic deposition

Sneak current is one of the main bottlenecks for dense crossbar array resistive random access memory. This study reports highly non-linear resistive switching characteristic from Ce_0.9Y_0.1O₂/TiO₂ bi-layer (1S/1R device) structure, fabricated by photochemical metal-organic deposition, as a solution for sneak current issue. Ce_0.9Y_0.1O₂ material, possessing oxygen vacancies, was used as a potential barrier as well as oxygen reservoir which rectified the current of low resistance state without an electrical breakdown in 1S/1R device. TiO₂ was adopted for resistive switching property, and TiO₂ layer having mixed phase (anatase and brookite) showed typical diode switching behavior. The photochemical reaction of photochemical metal-organic deposition process and phase formation were monitored and established using by Fourier-transform infrared spectroscopy and X-ray diffraction, respectively. The 1S/1R device showed highly non-linear resistive switching characteristic, large on/off ratio of above three orders of magnitude with low operating current.