학술논문
SRAM cell reliability degradations due to cell crosstalk
Document Type
Conference
Author
Source
2010 IEEE International Integrated Reliability Workshop Final Report Integrated Reliability Workshop Final Report (IRW), 2010 IEEE International. :129-132 Oct, 2010
Subject
Language
ISSN
1930-8841
2374-8036
2374-8036
Abstract
The capacitance between adjacent SRAM cells due to defectivity can increase in smaller geometry technologies. However, the abnormal behaviors due to such defective capacitance in SRAM are often neglected and can cause NTF (No Trouble Found) failures. The effective testing or calibration methods for such capacitance due to defects are not easily available in today's manufacturing. In this paper, a 3-D field solver was used to see the potential ranges of the defective capacitance. The crosstalk AC current through the coupling capacitance, which is referred to as cell coupling capacitor (C CCP ) is newly modeled as a current source to build modified SNM (Static Noise Margin). The two metrics, SNM and VDD MIN show that the reliability under the C CCP can be significantly degraded during memory operations. Even with a marginal C CCP , SNM variation is 40mV at a read operation and VDD MIN shift is 110mV at a write operation in a 65nm SRAM cell.