Impact of High-κ TaO_x Thickness on the Switching Mechanism of Resistive Memory Device Using IrO_x/TaO_x/WO_x/W Structure

摘要

The impact of switching layer thickness on the resistive memory performance and uniformity has been investigated in a simple stack of IrO_x/TaO_x/W fabricated. The formation of amorphous TaO_x and nanocrystalline WO_x layers are confirmed from HRTEM image. Bipolar resistive switching memory characteristics with small set/reset and large memory window are observed in all devices after electroforming. The observed TaO_x thickness independence of set/reset and low resistance state (LRS) is attributed to the formation of localized nano-filament in TaO_x layer. Cumulative probability plot shows tight distribution of LRS. Good data retention with a large resistance ratio of >10~3 at 85℃ is obtained.