| 摘要 |
PURPOSE:To contrive the extension of the time of holding the memory of cells at end parts by a method wherein the array of thin films THIN is provided in an oxide thick fim along the array of memory cells or the neighborhood of the end parts of a memory cell mat MCA, further N-layers are provided on this region, and thus a + potential is given. CONSTITUTION:1 bit cells are constituted of e.g. MISFETs and capacitors C, and each cell is arranged in a matrix form along word lines W and data lines DL resulting in the formation of the mat MCA. The time of holding information by the cell array (C21, C31... and C12, C22...continuous to W1, W2) at the end parts of the MCA is shorter than that by the central part. Immediately in the neighborhood of the cell array continuous to the word lines W1 and W2, recesses are arranged on the oxide film 2, then N<+> layers 5 are provided on a P type substrate and connected to power souces +VDD. Stress reduces on the substrate surface of the left side of C31, further leakage remarkably reduces in the presence of the N<+> layers 5 of fixed potential, and minority carriers flowing in from the outside into the end parts of the MCA are absorbed by the layers 5. Thereby, the time of holding memory is equalized at the central part and end parts of the MCA. |
