Published online by Cambridge University Press: 28 February 2011
Alkoxide-derived silica coatings were deposited on fused silica by dip coating. The samples were covered with a metal film to absorb the infrared radiation from an Nd:YAG laser. Coupling the laser power to the coating produced localized surface heating on the samples. By scanning the sample across the beam's path, channels in the coating were formed. The channels varied from 150 μm to 600 μm wide and from 200Å to 1000Å deep depending on the laser power and the translation speed. The size and shape of the channels also depended on the composition of the sol-gel coating. Optical microscopy showed that there were no cracks in either the substrate or in the coating on the micron scale. SEM revealed cracks on the nanometer scale in the laser fired coatings and no cracks in the unfired coatings. Ellipsometry showed that the index of refraction increased with increasing depth of the channels.
Full text views reflects PDF downloads, PDFs sent to Google Drive, Dropbox and Kindle and HTML full text views.