Aluminum oxide thin dielectric film formation under elevated gravity conditions

In an attempt to grow low defect, dense crystalline aluminum hydrous oxide [AlO(OH)] films with better dielectric properties, hydration experiments on a high purity, high cubicity aluminum foil were conducted in deionized water at 85 °C under high gravity conditions. Fields from 100 up to 14,100 g and reaction times from 1 min up to 6 h were used. The films obtained were examined by field emission-scanning electron microscopy and X-ray diffraction. Hydration for up to 30 min using g-forces up to 3000 g showed the presence of only one crystalline phase with particle size 20–30 nm identified as pseudo-boehmite. A second phase, bayerite, was found to be growing from the pseudo-boehmite film at times greater than 30 min using fields above 5000 g.