Printable Nanoparticle Superlattice Monolayer via Interfacial Assembly: Toward High‐Performance Multilevel Nanocrystals Floating‐Gate Memory

Abstract Large‐area, ordered nanoparticle (NP) films are essential for advanced electronics, particularly in applications that necessitate precise charge control, such as nanocrystals floating‐gate (NCFG) memories. The ordered NPs can enhance quantity/spatial distribution uniformity of storage sites and minimize structural defects. Nevertheless, their in‐situ fabrication remains challenging. Herein, a steady‐state printing strategy is reported for fabricating a large‐area, closely packed superlattice monolayer composed of Au@SiO ₂ core‐shell NPs via interfacial assembly. The Au core for excellent charge trapping and the SiO ₂ shell for optimal charge tunneling and solvent resistance, enabling orthogonal printing. A phenyltriethoxysilane monolayer is modified onto the SiO ₂ surface to optimize charge trapping/release dynamics, and a vertically phase‐separated polystyrene interlayer is introduced to mitigate interfacial trap states, ensuring efficient charge transport. Additionally, a highly oriented semiconductor active layer is achieved via direct‐ink‐writing fluid shearing. The synergistic integration of these functional layers results in a 8‐level (identical to reported maximum level of NCFG memory) memory device characterized by a large memory window (≈70 V, highest under comparable bias), high endurance (>200 cycles), and long retention (>10 ⁴ s). This work provides a scalable solution‐processed method for constructing functional nanoarchitectures and optimizing interface design, demonstrating its potential for next‐generation nanoelectronics.