| 摘要 |
PURPOSE: A non volatile memory(NVM) device is provided to improve a program/erase characteristic by increasing the surface area of a unit cell area, and to reduce occurrence of over-erase when the device operates by decreasing a cell area. CONSTITUTION: A semiconductor substrate(11) includes an active region defined by an isolation layer(12). A source region and a drain region are formed in the active region of the semiconductor substrate, separated from each other by a predetermined interval. A gate oxide layer(14) is formed on the active region of the semiconductor substrate. A polysilicon layer(15) operates as a floating gate, formed on the gate oxide layer between the source region and the drain region. The first oxide layer(17) is formed on a part of the gate oxide layer and the polysilicon layer. The first metal layer(18) is bent and formed on a part of the polysilicon layer exposed through the first oxide layer and on a part of the first oxide layer, operating as a floating gate and electrically connected to the polysilicon layer. The second oxide layer(19) is formed on the metal layer and on the exposed upper surface of the first oxide layer. The second metal layer(20) is bent and formed on a part of the upper surface of the second oxide layer to confront the first metal layer, operating as a control gate. A metal interconnection(22) is connected to the second metal layer and the source/drain region, respectively.
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