Interferometric patterning of the azo-polymers surface

Direct patterning of the polymeric surface, using a Talbot interferometer, was the solution for nanostructuring the polymers using UV short coherence laser radiation. Using the 355 nm radiation from a Nd:YAG laser, as a light source, a more flexible and controllable setup, was developed for direct patterning of azopolymer films by interference. With a grating like beam splitter we used the interference of (0, +1) or (+1,-1) diffraction orders to obtain an interference pattern. The two beams are superimposed using two parallel mirrors. In this way, controllable patterns having variable grating pitch can be obtained. The article describes the setup and some surface patterning results obtained on an azo-polymer (polysiloxane modified with azobenzene and naphthalene).