The future of 3D NAND flash technology
3D NAND flash has become the foundational non-volatile storage platform of the AI era, underpinning workloads from model training to large-scale inference and cold data archival. With roadmaps now targeting kilolayer stacks and tens of trillions of devices per die, scaling is no longer governed primarily by process integration or lithography. Instead, it is increasingly constrained by the physics of charge storage itself: lateral charge migration, electrostatic coupling, read disturb, and transport limitations are entering a margin-limited regime. In this regime, their collective interaction, not any single mechanism, compresses operating margins with each generation. In this Perspective, we examine these converging bottlenecks and argue that sustaining NAND scaling will require application-specific co-optimization rather than a monolithic device roadmap. In this framework, conventional charge-trap flash, ferroelectric storage, alternative channel materials, and system-level integration are best viewed as complementary solutions targeted to distinct tiers of data-centric computing.