Cluster-Assisted Mesoplasma Chemical Vapor Deposition for Fast Epitaxial Growth of SiGe/Si Heterostructures: A Molecular Dynamics Simulation Study.

Co-condensation of mixed SiGe nanoclusters and impingement of SiGe nanoclusters on a Si substrate were applied using molecular dynamics (MD) simulation in this study to mimic the fast epitaxial growth of SiGe/Si heterostructures under mesoplasma chemical vapor deposition (CVD) conditions. The condensation dynamics and properties of the SiGe nanoclusters during the simulations were investigated first, and then the impingement of transient SiGe nanoclusters on both Si smooth and trench substrate surfaces under varying conditions was studied theoretically. The results show that the mixed nanoclusters as precursors demonstrate potential for enhancing epitaxial SiGe film growth at a high growth rate, owing to their loosely bound atomic structures and high mobility on the substrate surface.

Maze-solving in a plasma system based on functional analogies to reinforcement-learning model.

Maze-solving is a classical mathematical task, and is recently analogously achieved using various eccentric media and devices, such as living tissues, chemotaxis, and memristors. Plasma generated in a labyrinth of narrow channels can also play a role as a route finder to the exit. In this study, we experimentally observe the function of maze-route findings in a plasma system based on a mixed discharge scheme of direct-current (DC) volume mode and alternative-current (AC) surface dielectric-barrier discharge, and computationally generalize this function in a reinforcement-learning model.

Study on liquid-like SiGe cluster growth during co-condensation from supersaturated vapor mixtures by molecular dynamics simulation.

Based on the co-condensation processes in the Si-Ge system upon cooling, as determined by molecular dynamics (MD) simulation, we explored the mixed cluster growth dynamics and structural properties leading to the synthesis of liquid-like SiGe nanoclusters. The results indicated that the cluster size quickly increased to large clusters by the coalescence of transient small clusters in the growth stage during co-condensation. The transient clusters at different temperatures were verified to have slightly Si-rich compositions and liquid-like structures.

Silicon nanorod formation from powder feedstock through co-condensation in plasma flash evaporation and its feasibility for lithium-ion batteries.

Si nanowires/nanorods are known to enhance the cycle performance of the lithium-ion batteries. However, viable high throughput production of Si nanomaterials has not yet attained as it requires in general expensive gas source and low-rate and multiple-step approach. As one of the potential approaches, in this work, we report the fast-rate Si nanorod synthesis from low-cost powder source by the modified plasma flash evaporation and the fundamental principle of structural formation during gas co-condensation.

Instantaneous formation of SiO nanocomposite for high capacity lithium ion batteries by enhanced disproportionation reaction during plasma spray physical vapor deposition.

Nanocomposite SiO particles have been produced by a single step plasma spray physical vapor deposition (PS-PVD) through rapid condensation of SiO vapors and the subsequent disproportionation reaction. Core-shell nanoparticles, in which 15 nm crystalline Si is embedded within the amorphous SiO matrix, form under typical PS-PVD conditions, while 10 nm amorphous particles are formed when processed with an increased degree of non-equilibrium effect. Addition of CH promotes reduction in the oxygen content of SiO , and thereby increases the Si volume in a nanocomposite particle.

High-rate and wide-area deposition of epitaxial Si films by mesoplasma chemical vapor deposition.

Homoepitaxial Si films have been deposited at a high rate of 200 nm s over a wide area of 20 mm × 80 mm by cluster-assisted mesoplasma chemical vapor deposition (MPCVD) on a moving substrate. The obtained epitaxial Si films exhibited a uniform roughness of 0.1-0.

High throughput production of nanocomposite SiO powders by plasma spray physical vapor deposition for negative electrode of lithium ion batteries.

Nanocomposite Si/SiO powders were produced by plasma spray physical vapor deposition (PS-PVD) at a material throughput of 480 g h. The powders are fundamentally an aggregate of primary ∼20 nm particles, which are composed of a crystalline Si core and SiO shell structure. This is made possible by complete evaporation of raw SiO powders and subsequent rapid condensation of high temperature SiO vapors, followed by disproportionation reaction of nucleated SiO nanoparticles.