A method for manufacturing a semiconductor device having a field-effect transistor, including forming a trench in a semiconductor substrate, forming a first insulating film in the trench, forming an intrinsic polycrystalline silicon film over the first insulating film, and introducing first conductive type impurities into the intrinsic polycrystalline silicon film to form a first conductive film. The subset can include one or more particular requested glyphs. The support comprises two braces. The crucial element is a flap of the chamber which only opens and closes in this area. The alkali metal sulfite, bisulfite or metabisulfite is preferably added to the animal feed, together with an inorganic sulfate.