3D-HIM: A 3D High-density Interleaved Memory for bipolar RRAM design

Because of its simple structure, high density and good scalability, resistive random access memory (RRAM) is expected to be a promising candidate to substitute traditional data storage devices, e.g., hard-disk drive (HDD). In a conventional three-dimensional (3D) bipolar RRAM design, an isolation layer is inserted between two adjacent memory layers. The fabrication of the isolation layer introduces the extra process complexity, increases fabrication cost, and causes some potential reliability issues. In this paper, we propose a 3D High-density Interleaved Memory (3D-HIM) design for bipolar RRAM, which can eliminate the need for forming isolation layers and further improve the density of the memory island. Meanwhile, we propose a Bi-Group Operation Scheme for 3D-HIM to access multiple cells among multiple layers and to avoid unexpected overwriting. The simulation results show that the proposed design is promising for a 3D stacking RRAM application with acceptable operation margin for a 32 × 32 × 8 array in a memory island. The sensing margin degradation and programming bias confine the size of the array due to sneak path conducting currents. We diminish impact of sneak path conducting current by applying a high Ron RRAM device which can be achieved by a small-scale RRAM device.