| 摘要 |
PURPOSE: A method for manufacturing a semiconductor EEPROM(Electrically Erasable Programmable Read Only Memory) device is provided to be capable of increasing the surface area of a floating gate for increasing the capacitance of a dielectric layer formed at the upper portion of the floating gate. CONSTITUTION: A tunnel oxide layer(34), a lower polysilicon layer, a silicon nitride layer and a photoresist pattern are sequentially formed at the upper portion of a semiconductor substrate(30). The lower polysilicon layer is partially etched and simultaneously carried out with an under-cut process by using the photoresist pattern as a mask. After removing the photoresist pattern, the lower polysilicon layer is etched by using an oxide pattern as a mask. Then, a curved floating gate(44) is formed by removing the oxide pattern and the silicon nitride layer. After sequentially forming a dielectric layer(46) and an upper polysilicon layer at the floating gate, a control gate(48) is formed by selectively patterning the resultant structure.
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