| 摘要 |
PURPOSE:To make the insulating film of gate oxide film, etc., to be formed on the surface of a substrate to be the films of good quality having no defect when field oxide films are to be formed according to the selective oxidation method by a method wherein directly after a CVD silicon nitride film to be used as the non-oxidizable film is formed, or directly before the field oxide films are to be formed, the films are heat treated in inactive gas. CONSTITUTION:A silicon oxide film 2 is formed on P type silicon substrate 1, and then the silicon nitride film 3 of the degree of 1,000Angstrom thickness to be used as the non-oxidizable film is deposited according to the CVD method, for example. The silicon nitride film 3 is heat treated in inactive gas of 1,000 deg.C in succession. Then, oxidation is performed in a wet oxygen atmosphere at 1,000 deg.C using the silicon nitride film 3 as the mask to grow the field oxide films 6 of 1.0mum thickness. By the treatment in inactive gas before oxidation thereof, binding of atoms in the silicon nitride film 3 is intensified, and reaction of the oxidizing agent (steam and oxygen) to diffuse in the silicon nitride film 3 during field oxidation with the nitride film 3 is suppressed. |
