Abstract: A method of producing so-called SOI structures according to this invention includes the step of forming an opening for seeding after an insulating layer of predetermined thickness has been formed on a first monocrystal silicon layer. Further, a non-monocrystal layer, e.g., a polycrystal silicon layer is formed on the surface of the insulating layer. The surface of the polycrystal silicon layer is smoothed as by grinding. A reflection-preventive film is formed on the smoothed surface of the polycrystal silicon layer. The reflection-preventive film has a thin film region whose reflectance is substantially zero and a thick film region having a predetermined reflectance. During laser annealing, the reflection-preventive film produces a predetermined temperature distribution in the polycrystal silicon layer.