High Performance MAHAHOS Memory Devices: Charge Trapping and Distribution in Bandgap Engineered Structure

In this paper, we investigate the MAHAHOS memory devices featuring a 2 nm Al<sub>2</sub>O<sub>3</sub> interfacial layer in the middle of the HfO<sub>2</sub> trapping layer. We explore the electrostatic force microscopy (EFM) technique to confirm that the Al<sub>2</sub>O<sub>3</sub> interfacial layer in trapping layer structure improves charge trapping capability by introduction of interfaces. The modulation of trapped charge distribution is proved by investigating the effect of varying the inserted Al<sub>2</sub>O<sub>3</sub> layer position on electrical characteristics. As a result of bandgap engineering, the MAHAHOS (HAH 5/2/5) device shows optimal performance of 9.2 V memory window, improved high temperature retention and flat endurance up to 10<sup>5</sup> cycles.