Nanometer-Scale ${\rm HfO}_{x}$ RRAM

HfOx-based resistive random access memory with an active area down to few nanometers in diameter is fabricated and characterized. Scaling trends for forming and switching characteristics are presented. For the smallest device with an active area of few nanometers in diameter, ac switching endurance of 10
⁸
cycles with more than 100 × resistance window is demonstrated. In addition, multiple resistance states are shown to be stable after 10
⁵
read cycles and 10
⁵
s baking at 150
^°
C.