The effects of different electrodes and surface oxygen plasma treatment for switching behavior on tri-layer Resistive Random Access Memory

The resistive random access memory (RRAM) with ZrO
₂
/ZnO/ZrO
₂
stacked structure have been fabricated on TaN-coated Si substrate in this work. The resistive switching layers ZnO and ZrO
₂
which are high-k materials are prepared by sol-gel method. When Al is deposited as top electrode, the operation electric field is lower than Ti-based device. But Ti-based device is more stable on low resistive state (LRS). The data retentions of all devices maintain over 10
⁴
seconds. After the substrate are treated by oxygen plasma, the surfaces become hydrophilic. The adhesion between TaN and solution-based oxide is improved. The electrical properties are also better than the ones without plasma treatment. The results of scanning electron microscope (SEM) and X-ray diffraction (XRD) can confirm that the devices were built successfully. In summary, the devices behave well under oxygen plasma treatment. The choice of the electrode depends on the different situations.