| 摘要 |
PROBLEM TO BE SOLVED: To provide a gate formation method of a flash memory device for preventing attacks from being generated in the active region of a semiconductor substrate by etching while adjusting a recipe when etching a dielectric film. SOLUTION: The gate formation method comprises a process for forming a tunnel oxide film and a first polysilicon film at an active region demarcated in the semiconductor substrate 100, and for forming an element separation film 106 at a field region; a process for laminating a dielectric film, a second polysilicon film, a tungsten silicide film, and a hard mask film at the upper portion of an entire structure including the active region and the field region; a process for etching prescribed regions in the hard mask film, tungsten silicide film, and second polysilicon film for exposing the dielectric film; a process for removing the upper portion of the exposed dielectric film; a process for partially removing the first polysilicon film in the active region for forming the horn of the dielectric film; a process for partially removing the first polysilicon film and the horn of the dielectric film; and a process for removing the horn completely. COPYRIGHT: (C)2007,JPO&INPIT
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