Intrinsic switching variability in HfO<inf>2</inf> RRAM

Abstract

In this work, we present a systematic electrical characterization of TiN\HfO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> \Hf\TiN RRAM elements from the variability perspective. Variability of both programmed resistance values and switching triggering voltages has been evaluated on small scaled cells in a wide operating current range (2μA till 500μA's), for different oxide stacks, in DC and pulsed conditions. For the first time device-to-device and cycle-to-cycle variability are thoroughly compared as well as the impact of different oxygen vacancy profiles. Increase of variability in low current operation is also elucidated.