Highly Reliable Memory Architecture Using Adaptive Combination of Proactive Aging-Aware In-Field Self-Repair and ECC

Reliability of embedded memory is critical for system-on-chips (SoCs). Aging-induced faults manifest in field, and they affect the reliability of embedded memories which occupy the most area of an SoC. By performing a proactive approach that repairs aged memory words in use, the probability of fault occurrence should be minimized. In this paper, we proposed an in-field strategy that proactively repairs aged words as well as correctable words. The reliability is enhanced further by combining an aging test, an in-field repair, and an error correction technique. An adaptive reconfiguration of the memory words, including aged words, correctable words, and uncorrectable words, is implemented with small overhead. A 3-state model that identifies memory cells as healthy, aged, or faulty is newly introduced, and the reliability evaluation using this model demonstrates the effectiveness of the proposed strategy.