The Impact of Parasitic Capacitance on the Memory Characteristics of 2T0C DRAM and New Writing Strategy

In this work, we systematically study the impact of capacitive coupling effect on the memory characteristics of 2T0C DRAM by both theoretical modeling and experiments. Then, based on the insights on capacitive coupling, we propose a new writing strategy for 2T0C DRAM, which can effectively enhance the memory window and retention at the same operation voltage. Finally, we demonstrate a high performance ZnO-based 2T0C DRAM cell with retention >1000 s under criterion of $\Delta \text{V}_{\text {SN}}$ = 0.1 V. Through the proposed new method, the retention of 2T0C DRAM cell can be improved from 1200 s to >10000 s under criterion of $\text{V}_{\text {SN}}$ drop to a failure voltage of 0.5 V.