Material instabilities in the TaOx-based resistive switching devices (Invited)

Oxide-based resistive switching devices offer an attractive set of characteristics for embedded memories and neuromorphic computing. However, their endurance is limited with the origin of failure mechanisms not firmly established. Transmission electron microscopy results on
$\text{TiN}/\text{TaO}_{\mathrm{x}}/\text{TiN}$
structures suggest that the primary reason is the intrinsic instability of
$\text{TaO}_{\mathrm{x}}$
in the middle of the composition range. This material separates into Ta- and O-rich phases that affect the filament morphology and can result in either stuck-in-high or stuck-in-low resistance state failure. An additional factor affecting endurance of switching devices is the interdiffusion at the electrode-functional oxide interfaces.