3D Memory Cell Interconnect Layout for Capacity and Reliability

The patent transitions from two-dimensional memory cell arrangement to three-dimensional arrangement by stacking multiple layers of memory cells vertically. This includes forming alternating layers of first and second sacrificial materials, creating channel structures that extend through multiple gate electrode layers, and establishing vertical interconnections that penetrate through stacked layers, thereby significantly increasing storage capacity per unit area.

The memory device is divided into multiple functional layers including first and second sacrificial material layers, alternating interlayer insulating layers, channel structures, and gate electrode layers. Each layer serves a specific function and can be independently formed and patterned, allowing complex three-dimensional structures to be built through sequential processing steps while managing overall device complexity.

Through-contact plugs are formed to extend through the entire stack structure before final interconnection layer formation. Dummy contacts are strategically positioned and formed in advance to compensate for potential misalignments or variations in subsequent processing steps. These preliminary structures ensure reliable electrical connections even when manufacturing tolerances cause slight deviations in layer alignment.

The patent incorporates dummy contacts as compensatory features that provide electrical connection pathways even if primary connection points fail due to manufacturing variations. The alternating sacrificial material layers and interlayer insulating layers are designed with sufficient thickness margins to accommodate processing variations, cushioning against potential connection failures and ensuring robust reliability.