Fullerene-Based Hybrid Devices for High-Density Nonvolatile Memory

We demonstrate a CMOS-compatible, nonvolatile, hybrid-memory device using fullerenes as a floating gate. In the hybrid MOS capacitors, organic fullerene molecules were encapsulated between inorganic oxides, i.e., SiO₂ as a tunnel oxide and HfO₂ as a control oxide. Aluminum was e-beam deposited on the fullerenes and spontaneously oxidized to act as a nucleation layer for the HfO₂ control oxide. Material characterization confirmed the presence of fullerenes and high-k dielectric in the gate stack. Electrical characterization verified the memory operation of the devices. Finally, the molecular orbital energies of the fullerene molecules in the gate stack were estimated.