An Efficient BIRA Utilizing Characteristics of Spare Pivot Faults

Abstract

The current growth of micro-semiconductor technologies requires that an effective solution be found to address the yield and reliability issues associated with embedded memories. A common solution is built-in redundancy analysis (BIRA), which is utilized to guarantee reasonable memory yields. The most common form of BIRA is a module that stores and analyzes fault addresses with a 2-D spare architecture. When the performance of BIRA is evaluated, numerous different parameters are considered, such as repair rate, area overhead, and analysis speed. Because there is a tradeoff between these criteria, many BIRA approaches have been studied so that an ideal BIRA can be found. A novel BIRA approach that focuses on a 100% repair rate and a minimal area overhead is proposed in this paper. In the fault collection phase, the proposed BIRA stores only the essential part of fault addresses in content addressable memories (CAMs), with the rest of the fault addresses being stored in spare memories. After the fault collection phase, a redundancy analysis procedure is performed with the minimum amount of fault information that is stored in the proposed CAM structure. By doing so, the proposed BIRA algorithm can repair all repairable faulty memories while maintaining a minimal area overhead. Our experimental results confirm that the proposed approach exhibits outstanding performance for area overhead, especially when compared to other BIRA approaches that have 100% repair rates.