Abstract
As microelectronic feature sizes are scaled down, the soft failure rate has increased. Additionally the characteristics and distribution of Dynamic Random Access Memory (DRAM) data retention time and write recovery time (tWR) are getting worse. As a result of this failure analysis, we revealed that the major contributors are caused by the interference noise, resultant from decreasing separation distance between nodes and the signal line noise increasing. This paper gives a detailed analysis of the problem caused by the coupling effects. We investigated the cause of soft noise by simulation and proposed calculation of sensing margin change by interference noise. Finally, we expect that a design improvement to reduce the magnitude of interference noise will result in overall improvement when implemented in the test vehicle.
