Technology frontiers towards the 21st century: embedded DRAM and the system LSIs-process, circuits, and design technology

The development of silicon technology is opening the new era of "systems on silicon". That is, a large-scale memory will be integrated with a CPU and other logic macros. These kinds of chips, so-called system LSIs, have a promising future, especially in mobile systems for advanced multimedia applications since they feature high data-transfer rate, low I/O power dissipation, and system miniaturization. However, such a system-oriented LSI causes new technical problems such as increases in subthreshold leakage current, process cost, and design complexity. It will also have a significant influence on the business strategies of LSI makers. This paper reviews the features and issues of embedded DRAMs and system LSIs and then introduces advanced technologies for designing and fabricating them.