| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To obtain a structure of a highly reliable semiconductor memory device and the manufacturing method thereof wherein the increase of the number of manufacturing processes for constituting the semiconductor memory device is eliminated, and further, its read by using a low voltage is made possible. <P>SOLUTION: The semiconductor memory device has an N-channel type MOS transistor 53 and a MONOS-type memory transistor 56 in a single P-well region 11. In the manufacturing method of the semiconductor memory device, the thickness of the effective oxide film of a memory insulation film 75 constituting the MONOS-type memory transistor 56 is made smaller than the thickness of a gate oxide film 74 constituting the N-channel type MOS transistor 53, and the initial threshold voltage of the MONOS-type memory transistor 56 is made lower than that of the N-channel type MOS transistor 53. <P>COPYRIGHT: (C)2003,JPO</p> |
