SEMICONDUCTOR INTEGRATED CIRCUIT DEVICE AND MANUFACTURE THEREOF

摘要

PROBLEM TO BE SOLVED: To provide a technology which can realize the high-reliability DRAM by improving the refleshing characteristics without complicating the manufacturing process. SOLUTION: A p-type semiconductor region 24 for adjusting a threshold voltage is formed only at a p-type well 4 on the side of a data line 18 of a memory-cell selecting MISFET(metal-insulator semiconductor field-effect transistor) Qs. The impurity concentration of the p-type well 4 on the side of an information storing capacitor element is set so that the concentration is lower than the impurity concentration of the p-type well on the side of the data line 18. This, 1.1 V of the threshold voltage of the memory-cell selecting MISFET Qs is obtained. An the same time, the junction electric-field intensity an the end of a gate electrode 7 on the side of the information storing capacitor element can be decreased.