Discrete electron storage and retention in single α-MoO3 nanocrystals

The development of high-density, energy-efficient nonvolatile memory (NVM) devices can benefit from the integration of novel charge-trapping materials with nanoscale performance. Here, we demonstrate the synthesis of orthorhombic-phase α-MoO 3 nanoparticles (NPs), achieved via solution processing, and their incorporation as discrete High-k charge trapping sites within a Metal-Oxide-High-k-Oxide-Semiconductor (MOHOS) architecture employing ultrathin Al 2 O 3 tunnel and blocking layers. Conductive Atomic force microscopy (cAFM) and Kelvin probe force microscopy (KPFM) were used to directly correlate mapping of both topography and local electrical behavior at the single-NP level. cAFM I-V curves over individual MoO 3 NPs revealed charge trapping/detrapping with threshold shifts around 1 V. KPFM confirmed localized electrostatic potential shifts corresponding to the storage of ∼10-30 electrons per NP, with independent transport-based (cAFM) and electrostatic (KPFM) estimates agreeing to within a factor of two. By combining discrete trapping scalability and low-power operation, single MoO 3 NP capacitor geometry delivers reliable reversible storage. These single-node charge states provide a materials-level basis for discrete-trap memory with potential for multi-level storage.