| 摘要 |
PROBLEM TO BE SOLVED: To provide a method of manufacturing a semiconductor apparatus which enables efficient formation of gate insulating films of mutually different film thicknesses, while enhancing an element isolation function of an insulating film. SOLUTION: The method of manufacturing a semiconductor apparatus is provided, in which nonvolatile memory elements and logic elements are mixedly mounted. The method comprises steps of forming substrate protection films 202, 203 used in forming an element isolation film 207 on a silicon substrate 201, forming a tunnel insulating film 209 in a flash cell region while allowing the substrate protection film to remain in a logic region, forming an intermediate oxide film 214 at a thick-film gate portion while allowing the substrate protection film to remain at a thin-film gate portion, and forming a gate insulating film 216 while removing the substrate protection film from the thin-film gate portion. In particular, a gate insulating film 217 formed at the thick-film gate portion is formed through two oxidation processes among which the second oxidation process is carried out simultaneously with an oxidation process for the gate insulating film 216 formed in the thin-film gate region. COPYRIGHT: (C)2004,JPO&NCIPI
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