High-capacity rotary drum for atomic layer deposition onto powders and small mechanical parts in a hot-walled viscous flow reactor
| Autor: | Joseph A. Libera, Jeffrey W. Elam, Matthias J. Young, Anil U. Mane, Matthew W. Coile |
|---|---|
| Rok vydání: | 2020 |
| Předmět: |
Materials science
Silicon Silica gel Diffusion chemistry.chemical_element 02 engineering and technology Surfaces and Interfaces engineering.material 010402 general chemistry 021001 nanoscience & nanotechnology Condensed Matter Physics 01 natural sciences 0104 chemical sciences Surfaces Coatings and Films chemistry.chemical_compound Atomic layer deposition Surface area Coating chemistry Fluidized bed engineering Gravimetric analysis Composite material 0210 nano-technology |
| Zdroj: | Journal of Vacuum Science & Technology A. 38:052403 |
| ISSN: | 1520-8559 0734-2101 |
| Popis: | Atomic layer deposition (ALD) is uniquely capable of providing uniform thin-film coatings on powder substrates, but powder processing has historically required an ALD reactor designed specifically for powders—e.g., a fluidized bed. Tubular hot-walled viscous-flow reactors commonly employed in laboratory-scale ALD research for coating planar substrates such as silicon have been employed previously to coat gram quantities of powder spread out in a thin layer on a tray, but larger quantities of powder introduce long diffusion pathways where reactants are unable to percolate to the bottom of the powder bed to provide uniform coating in reasonable time periods. In this work, we report a rotary drum with a capacity of 100s of grams that is compatible with conventional tubular hot-walled ALD reactors and provides uniform coatings on powders in viscous flow operation. We benchmark this system using Al2O3 ALD with trimethylaluminum and water. We examine the effect of rotation speed and powder quantity on saturation time via in situ quadrupole mass spectroscopy measurements and gravimetric analysis. The rotary drum we report is able to provide homogenous coating of up to 75 g of silica gel powder with a total surface area of ∼1500 m2 in viscous flow operation with precursor utilization as high as 70%. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|