Low-Power, High-Performance, Non-volatile Inkjet-Printed HfO₂-Based Resistive Random Access Memory: From Device to Nanoscale Characterization

Low-power, high-performance metal–insulator–metal (MIM) non-volatile resistive memories based on HfO 2 high- k dielectric are fabricated using a drop-on-demand inkjet printing technique as a low-cost and eco-friendly method. The characteristics of resistive switching of Pt (bottom)/HfO 2 /Ag (top) stacks on Si/SiO 2 substrates are investigated in order to study the bottom electrode’s interaction with the HfO 2 dielectric layer and the resulting effects on resistive switching. The devices show low Set and Reset voltages, high ON/OFF current ratio, and relatively low switching current (∼1 μA), which are comparable to the characteristics of current commercial CMOS memories. In order to understand the resistive switching mechanism, direct structural observation is carried out by field-emission scanning electron microscopy (FE-SEM) and high-resolution transmission electron microscopy (HRTEM) on cross-sectioned samples prepared by focused ion beam (FIB). In addition, electron energy loss spectroscopy (EELS) inspections discard a silver electro-migration effect.