Channel Modeling for 2TOC Gain-Cell eDRAM

The rising of big data and artificial intelligence applications requires embedded memory with higher density, lower power consumption, and wider bandwidth. Embedded dynamic random-access memory (eDRAM) are one of the promising embedded memory technologies. Recent advances in thin-film amorphous oxide semiconductor field-effect transistors (AOSFET) have enabled two-transistor-zero-capacitor (2TOC) gain cell eDRAMs to have three-dimensional integration capability and ultra-long retention time. However, 2TOC gain cell eDRAMs are still facing read accuracy challenges. In this paper, we explored the statistical distribution characteristics of storage node (SN) charges during the retention and read phases by conducting perturbation analysis on the 2TOC GC eDRAM. Furthermore, we proposed a retention channel model and a read channel model for the 2TOC GC eDRAM. The Monte Carlo circuit simulation results indicate that both the retention channel and read channel can well describe the statistical properties of retention errors and read errors in the 2TOC GC eDRAM. Both channel models can be used to enhance the overall reliability of the GC eDRAM.