An Effective Spare Allocation Methodology for 3D Memory Repair with BIRA

Three-dimensional (3D) memory is widely developed to fulfill the ever-increasing memory densities. For the high reliability of 3D memory, the traditional spare structures that consist of simple rows and columns have a difficulty to maximize the efficiency of spare allocation. Therefore, various spare structures are adopted to achieve a high repair rate improvement for multiple banks memory. However, the previous studies have not proposed any methodology to allocate various spare structures with BIRA. For this reason, a new effective spare allocation methodology for the pre-bond and the post-bond repair is proposed. Also, the methodology can be verified by six representative various spare structures with the sequential allocation BIRA.