Synergistic Reliability and Yield Enhancement Techniques for Embedded SRAMs

Single isolated fault (SIF) stands for about 60%-70% of the total number of defects and is rather redundancy hungry since a spare row or a column is required for repairing each SIF. Therefore, manufacturing yield will decrease if we do not allocate sufficient spare resources. In this paper, instead of the traditional fault replacement techniques, synergistic techniques that integrate both fault replacement and fault masking techniques are proposed. With our approaches, SIFs are masked instead of the traditional replacement for repairing. For other minor fault types (e. g., faulty rows and faulty columns), the fault replacement technique is used as usual. According to simulation results, repair rates can be improved significantly. The proposed techniques can be integrated with the conventional built-in self-repair with nearly negligible hardware overhead.