| 摘要 |
<p>A method for fabricating a NAND flash memory device is provided to increase the effective channel length of a gate by recessing a semiconductor substrate of a source select line, a drain select line, a source line and a bitline selectively or generally. An ion implantation process is performed on a portion of a semiconductor substrate(100) in which a source select line and a drain select line are to be formed. After the portion of the semiconductor substrate for forming the source select line and the drain select line is recessed, a heat treatment is carried out. After a tunnel oxide layer, a capping polysilicon layer(106) and a first hard mask layer are deposited on the recessed semiconductor substrate by a predetermined thickness, a predetermined region of the resultant structure is etched to form a trench. After a first insulation layer is deposited on the resultant structure to fill the trench, the first insulation layer is removed to expose the upper part of the first hard mask layer so that an isolation layer is formed. After a first polysilicon layer(112) is deposited on the resultant structure, a predetermined region of the first polysilicon layer is etched.</p> |
