Memory device structure and method

Abstract

Memory cells, semiconductor devices, semiconductor stacked structures, and fabrication methods are provided. An example memory cell includes a capacitor and a transistor stacked over the capacitor in a compact configuration. The capacitor includes a floating gate, a high-k dielectric layer, and a metal gate. The metal gate extends horizontally from a first sidewall to a second sidewall and vertically from a bottom surface to a top surface. The transistor includes the metal gate and a gate dielectric layer disposed on the metal gate. The gate dielectric layer includes two side portions respectively disposed on the two sidewalls of the metal gate and, and a top portion disposed on the top surface of the metal gate. The transistor further includes two separate S/D regions respectively formed on the two side portions of the gate dielectric layer, and a channel region formed on the top portion of the gate dielectric layer.