Improving Performance by Inserting an Indium Oxide Layer as an Oxygen Ion Storage Layer in HfO₂-Based Resistive Random Access Memory

This study investigates an improvement in memory characteristics through depositing an In
₂
O
₃
layer as an oxygen ion reservoir in the switching layer (SL) of resistive random access memory (RRAM). The deposition of In
₂
O
₃
, denoted as Pt/HfO
₂
/In
₂
O
₃
/TiN device, provides better memory characteristics including lower forming voltage (V
_F
), set/reset voltage (V
_SET
/V
_RESET
), larger memory window, and higher resistances with higher uniformity at low resistance state (LRS) and high resistance state (HRS), compared to the devices without the In
₂
O
₃
deposition, denoted as Pt/HfO
₂
/TiN device. The conduction mechanisms, verified through fitting current-voltage (I-V) curves, are consistent with the results of a varied temperature I-V experiment. Finally, a physical model is proposed to explain our observations.