| 摘要 |
PURPOSE:To prevent information breakage due to punch-through, by making trench regions of two facing memory cells be formed from one trench region and performing element isolation ranging from the bottom part to the side part in the central part of the trench. CONSTITUTION:Trench regions (capacitor formation trenches) of two facing memory cells A and B are formed from one trench region 12. An information charge accumulation part 20 in the memory cell A is formed in the left half of the region 12 and an information charge accumulation part 30 in the memory cell B is formed in the right half of the region 12. Separation of the memory cells A and B is performed ranging from the bottom surface part to the side part in the center of the trench region 12. Side walls of the facing trench regions can be removed in this way, so that a punch-through phenomenon can be prevented from occurring on these side wall parts. |
