ECC-ASPIRIN: An ECC-assisted post-package repair scheme for aging errors in DRAMs

Because of continuous scaling down to small dimensions, DRAM has become a main memory with high capacity and density. Because denser memories are likely to contain more errors, DRAM employs repair schemes that replace errors with good cells for yield enhancement of a memory. The conventional repair scheme covers only manufacturing-level errors. As DRAM wears out while operating in the field, to enhance the lifetime of a memory, we need to incorporate a post-package repair scheme into a memory system for repairing aging errors. In this paper, we propose a methodology that repairs aging errors in a memory during field operations. Using the memory yield and lifetime simulator, we evaluate the proposed repair method. Employing a 2GB DDR3 ECC-DIMM as a case study, we demonstrate that our post-package repair scheme improves the yield and the lifetime of a memory.