Conduction mechanisms and reliability characteristics in MgO resistive switching memory devices

In this work, the resistive switching memory devices based on MgO thin film were fabricated and investigated. A forming electric field of about 2.36 MV/cm is required to induce bipolar resistive switching characteristic of the Pt/MgO/Pt metal-insulator-metal (MIM) diodes. At room temperature, the set and reset electric fields are about 1.5 MV/cm and -0.9 MV/cm, respectively. After the electroforming process, the resistance ratio of high resistance state (HRS) and low resistance state (LRS) is on the order of 10⁵. The temperature dependence of current density-electric field (J-E) characteristics indicates that the dominant conduction mechanism is the hopping conduction and the Ohmic conduction in HRS and LRS, respectively. Accordingly, the hopping distance, trap energy level, and electron mobility in MgO films are obtained. In addition, the reliability characteristics of program/erase cycling endurance, data retention, and read durability of the MgO-based MIM memory devices were measured.