METHOD FOR FABRICATING NON-VOLATILE MEMORY DEVICE BY USING WAFER BONDING PROCESS

摘要

PURPOSE: A method for manufacturing a nonvolatile memory device is provided to integrate a lot of memory cells in a limited area on a wafer using a wafer bonding. CONSTITUTION: A first gate stack(110) for a first NAND string is formed on a first semiconductor substrate(100). A first insulation layer(130) is formed to cover the first gate stack. An ion implantation layer is formed in the second semiconductor substrate. The second semiconductor substrate is stacked on the first insulation layer. The first and second semiconductor substrates are bonded with the wafer bonding. The second semiconductor substrate under the ion implantation layer is set as a semiconductor layer(201). The surface roughness of the semiconductor layer is reduced by removing an oxide layer. A second gate stack(250) for a second NAND string is formed on the semiconductor layer.