Multireflection Effect on Formation of Periodic Surface Structure on an Si Film Melting-Crystallized by a Linearly Polarized Nd:YAG Pulse Laser Beam

Abstract

We investigated the multireflection effect on the formation of a periodic surface structure produced by a linearly polarized Nd:YAG laser beam of 532 nm on an Si film deposited on a glass substrate, as well as on heating rate in the film, compared with an excimer laser beam. From the theoretical calculation results, it was found that the formation of the periodic surface structure and heating rate strongly depended on film thickness or that they were influenced by the multireflection effect. The thickness most effective for forming the periodic surface structure and heating rate was about 60 nm. Furthermore, we attempted to verify the calculation results by carrying out an experiment in which we checked whether the periodic structure was formed on the surface of the melting-crystallized Si films. As a result, the thickness range for producing the periodic surface structure was found to be from 50 to 70 nm, which were larger than the theoretical values of 40 to 60 nm.