Methanol Soaking Step

SEM was used to view the state and orientation of the 200 nm spheres on a silica surface.  There was a good amount of monolayer coverage (more than multi-layer), although those monolayers had line interruptions through out it.  A grid was used to find a spot which after soaking was performed could be found again for comparing the sphere positions.
After soaking the silica sample in methanol for 15 hours (overnight) the surface had a much deeper purple color.  When SEM was used to determine whether or not the soaking moved the spheres around significantly, it could be seen that the soaking had little to no effect on the position of the spheres, however not much could be said about the SDS on the sample surface.  From this information we can say that the soaking step can only be helpful, because the sphere positions did not change so if the SDS wasn't removed no harm was done to the sample.  If the SDS film was loosened or removed then when RIE is done there should be less of a mask from the SDS and the spheres should be able to create a better mask for creating the nanopillars.  All this is good news and hopefully next week or the week after, depending on the RIE availability, we will be able to try etching again with a shorter etch time and see what kind of shapes we can get!!  Exciting!!