| 摘要 |
PURPOSE:To prevent the reliability of a semiconductor device from declining by providing a polycrystalline silicon layer which is extended from the upper part of a thin insulating film formed on one part of a first impurity region through the upper part of a remaining part of an isolation region to a thick insulating layer. CONSTITUTION:In a MOS transistor where field oxide films 107A, 107B are used as gate insulating films, polycrystalline silicon layers 106A, 106B are formed on the upper part in one part of an active region including a first impurity region and on the upper part in one part of a thick insulating film (field oxide film) as the gate insulating film 108; a definite interval is formed between the first impurity region and the field oxide film. Accordingly, a positive electric charge to be generated by being induced by a negative electric charge generated when an abnormal voltage is impressed on an input voltage and a hot electron is injected into the field oxide film does not influence a depletion layer 112 in the first impurity region. By this setup, it is possible to form a device whose reliability is high. |
