Ultralow switching current in HfOx/ZnO bilayer with tunable switching power enabled by plasma treatment

Decreasing switching power of a memory cell to meet demands of further downsizing is feasible with several methods. However, effects of plasma treatment on switching current and power are scarcely investigated. We therefore replaced traditional single storage layer with a HfOx/ZnO bilayer and also treated its interface with argon plasma. The switching current could be suppressed to μA due to a Schottky barrier at the HfOx/ZnO interface. Additionally, argon plasma treatment on the interface enables tunability of switching power and current, which is attributed to the tunable barrier height with the absorbed oxygen species introduced by plasma treatment.