Demonstrate high Roff/Ron ratio and forming-free RRAM for rFPGA application based on switching layer engineering
The application of reconfigurable architectures in field programmable gate array (FPGA) has been addressed great concern by academic and industrial. However, fabricating a nonvolatile device for circuit routing configuration in connection block is still a great challenge. In this paper, a forming-free RRAM technology with high resistance R<inf>ON</inf>/R<inf>OFF</inf> ratio (∼10<sup>6</sup>) is developed for reconfigurable circuits connecting. The demonstrated RRAM with switching layer engineered Pd/Al<inf>2</inf>O<inf>3</inf>/HfO<inf>2</inf>/NiO<inf>x</inf>/Ni structure shows excellent performance, such as low variation, good retention (>10 years@85°C) and large drive current (>1mA). In addition, corresponding switching mechanism and how to improve RRAM's resistance R<inf>ON</inf>/R<inf>OFF</inf> ratio by material engineering and device structure optimization are also discussed.