Capacitor-Less 4F(2) DRAM Using Vertical nGaAs Junction for Ultimate Cell Scalability

In this work, we demonstrated capacitor-less 4F(2) 2-terminal InGaAs npn junction DRAM through careful device design. Using epitaxially grown InGaAs which have a steep junction, fabricated InGaAs bistable resistor (biristor) DRAM showed low voltage operation (similar to 2 V), fast switching speed (<:20 ns), long-term retention (10(3) s at 85 degrees C), and high endurance (>10(10) cycles) with a high sensing margin. Considering this feasibility study, we believe that InGaAs n(+)pn(+) junction DRAM could be a good technological option for future scalable 3D DRAM.