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Dielectric breakdown (DB) controls the failure, and increasingly the function, of microelectronic devices. Standard imaging techniques, which generate contrast based on physical structure, struggle to visualize this electronic process. Here in situ scanning transmission electron microscopy (STEM) electron beam‐induced current (EBIC) imaging of DB in Pt/HfO2/Ti valence change memory devices is reported. STEM EBIC imaging directly visualizes the electronic signatures of DB, namely local changes in the conductivity and in the electric field, with high spatial resolution and good contrast. DB is observed to proceed through two distinct structures arranged in series: a volatile, "soft" filament created by electron injection; and a non‐volatile, "hard" filament created by oxygen‐vacancy aggregation. This picture makes a physical distinction between "soft" and "hard" DB, while at the same time accommodating "progressive" DB, where the relative lengths of the hard and soft filaments can change on a continuum. [ABSTRACT FROM AUTHOR]

Modern microelectronic devices have nanoscale features that dissipate power nonuniformly, but fundamental physical limits frustrate efforts to detect the resulting temperature gradients. Contact thermometers disturb the temperature of a small system,while radiation thermometers struggle to beat the diffraction limit. Exploiting the same physics as Fahrenheit's glass-bulb thermometer, we mapped the thermal expansion of Joule-heated, 80-nanometer-thick aluminum wires by precisely measuring changes in density. With a scanning transmission electron microscope and electron energy loss spectroscopy, we quantified the local density via the energy of aluminum's bulk plasmon. Rescaling density to temperature yields maps with a statistical precision of 3 kelvin/hertz-1/2, an accuracy of 10%, and nanometer-scale resolution. Many common metals and semiconductors have sufficiently sharp plasmon resonances to serve as their own thermometers. [ABSTRACT FROM AUTHOR]

Using scanning transmission electron microscopy we image∼4nm platinum nanoparticles deposited on an insulating membrane, wherethe membrane is one of two electron-transparent windows separatingan aqueous environment from the microscope’s high vacuum. Uponreceiving a relatively moderate dose of ∼104 e/nm2, initially immobile nanoparticlesbegin to move along trajectories that are directed radially outwardfrom the center of the field of view. With larger dose rates the particlemotion becomes increasingly dramatic. These observations demonstratethat, even under mild imaging conditions, the in situelectron microscopy of aqueous environments can produce electrophoreticcharging effects that dominate the dynamics of nanoparticles underobservation. [ABSTRACT FROM AUTHOR]

Recently, silicon-based lithium-ionbattery anodes have shown encouragingresults, as they can offer high capacities and long cyclic lifetimes.The applications of this technology are largely impeded by the complicatedand expensive approaches in producing Si with desired nanostructures.We report a cost-efficient method to produce nanoporous Si particlesfrom metallurgical Si through ball-milling and inexpensive stain-etching.The porosity of porous Si is derived from particle’s three-dimensionalreconstructions by scanning transmission electron microscopy (STEM)tomography, which shows the particles’ highly porous structurewhen etched under proper conditions. Nanoporous Si anodes with a reversiblecapacity of 2900 mAh/g was attained at a charging rate of 400 mA/g,and a stable capacity above 1100 mAh/g was retained for extended 600cycles tested at 2000 mA/g. The synthetic route is low-cost and scalablefor mass production, promising Si as a potential anode material forthe next-generation lithium-ion batteries with enhanced capacity andenergy density. [ABSTRACT FROM AUTHOR]