Semiconductor memory device
US6992343B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | Oct 29, 2004 |
| Grant date | Jan 31, 2006 |
| Priority date | — |
| Expiry date | Oct 29, 2024 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S257/906
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A semiconductor memory device is provided which can achieve the high integration, ultra-high speed operation, and significant reduction of power consumption during the information holding time, by reducing the increase in the area of a memory cell and obtaining a period of the ultra-high speed readout time and ensuring a long refresh period at the time of the self refresh. A DRAM employing a one-intersection cell·two cells/bit method has a twin cell structure employing a one-intersection 6F2 cell, the structure in which: memory cells are arranged at positions corresponding to all of the intersections between a bit-line pair and a word line; and when a half pitch of the word line is defined as F, a pitch of each bit line of the bit-line pair is larger than 2F and smaller than 4F. Further, an active region in the silicon substrate, on which a source, channel and drain of the transistor of each memory cell are formed, is obliquely formed relative to the direction of the bit-line pair.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.