METHOD OF FABRICATING SEMICONDUCTOR DEVICE TO USE SIMULTANEOUSLY DUAL GATE INSULATING LAYER AND DUAL GATE POLYSILICON ELECTRODE

摘要

PURPOSE: A method of fabricating a semiconductor device is provided to improve reliability of the semiconductor device by using simultaneously a dual gate insulating layer and a dual gate polysilicon electrode. CONSTITUTION: A first gate insulating layer is formed on a semiconductor substrate(20) including a cell region and a peripheral circuit region. A plasma process for the first gate insulating layer is performed. A mask is formed thereon to expose only the cell region. The first gate insulating layer is removed from the cell region. The mask is removed therefrom. A third gate insulating layer(26) is formed on the cell region by an oxidation process. A second gate insulating layer(25) is formed on the peripheral circuit region.