Growth and characterization of high density stoichiometric SiO2 dot arrays on Si through an anodic porous alumina template

In this work, we present the fabrication and full characterization of stoichiometric SiO2 nanoisland arrays ( dots) on silicon, grown through an anodic porous alumina template. Atomic force and transmission electron microscopy (AFM, TEM) were used to characterize the morphology, size, size distribution and density of the dots as a function of the anodization time used. It was found that dot density is lower for very short anodization times, and it stabilizes after a certain time. The dot height increases rapidly after nucleation, reaching values of 8 - 10 nm. With prolonged oxidation the dots continue to nucleate to fill the available area on the silicon surface underneath the porous alumina, while the well developed dots grow in height and width, reaching saturation values at 14 and 55 nm respectively. X-ray photoelectron spectroscopy (XPS) and electron energy loss spectroscopy ( EELS) were used to investigate the stoichiometry and surface coverage of the dots.