US Patent 11574924 Memory cell fabrication for 3D NAND applications

Embodiments of the present disclosure provide an apparatus and methods for forming stair-like structures with accurate profiles and dimension control for manufacturing three dimensional (3D) stacked memory cell semiconductor devices. In one embodiment, a memory cell device includes a film stack comprising alternating pairs of dielectric layers and conductive structures horizontally formed on a substrate, and an opening formed in the film stack, wherein the opening is filled with a metal dielectric layer, a multi-layer structure and a center filling layer, wherein the metal dielectric layer in the opening is interfaced with the conductive structure.