| 摘要 |
<p>A method for manufacturing an NAND flash memory device is provided to reduce an area of a floating gate by forming a void at a center of the floating gate. A trench is formed by etching a tunnel oxide layer(102), a first polysilicon layer(104), a buffer oxide layer, a nitride layer, and a part of a semiconductor substrate(100). A slop is formed on a lateral surface of the nitride layer. An isolation layer(110) is formed within the semiconductor substrate by forming an insulating layer within the trench. A lateral surface of an upper part of the isolation layer is formed as a negative profile. A polysilicon layer is formed on an entire structure. A seam is generated within the polysilicon layer. The seam is formed as a void by performing a post-annealing process. Further, a slope of a side surface of the nitride layer is 84 - 87°C.</p> |
