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Conventional static random‐access memory (SRAM) suffers from high leakage power in advanced complementary metal‐oxide‐semiconductor nodes. Meanwhile, gain‐cell embedded dynamic random‐access memory (GC‐eDRAM) is an area‐efficient alternative to SRAM, although it requires periodic refresh cycles. In this regard, this study proposes a fin field‐effect transistor (FinFET)‐based 5T GC‐eDRAM bitcell that addresses the leakage power issue of SRAM while avoiding the bandwidth‐consuming refreshes of GC‐eDRAM. Furthermore, for the feasibility of scaling down transistors, the gain‐cell design is based on the FinFET, which overcomes short‐channel problems. The proposed 5T bitcell provides additional internal feedback relative to the 4T all‐nMOS fully depleted‐silicon on insulator (FD‐SOI) gain cell to ensure the static retention of both "1" and "0" data. The 2‐kB array was simulated by employing a 7‐nm FinFET predictive technology model (PTM) using HSPICE. The simulation results show that the proposed 5T bitcell (at 0.7 V) enables over 13× smaller data retention power and 10× area reduction compared to the 4T all‐nMOS GC‐eDRAM cell in a 28‐nm FD‐SOI technology. [ABSTRACT FROM AUTHOR]

In this paper, a SRAM cell structure which uses pMOS access transistors and predischarged bitlines is presented. By using the strained pMOS transistor technology, the degradation of the read static noise margin (SNM) at high supply voltages due to the aging, especially in the presence of symmetric stress, is suppressed. In contrast to conventional cell, the write margin of the proposed cell does not degrade considerably at low supply voltages. To assess the efficacy, the proposed cell is compared with conventional cell for two cases of unstrained and strained pMOS. A comparative study is performed using mixed mode device/circuit simulations for a gate length of 22 nm. The results show that the read SNM degradation due to the symmetric aging at the supply voltage of 1V is about 6% after three years for the proposed strained structure, while degradations are 14%, 12%, and 11% for the unstrained proposed structure, unstrained, and strained conventional structures, respectively. In addition, the proposed cell has both read and write cell sigma yields higher than six for supply voltages ranging from 1V down to 0.5V while the other structures have read or write yields less than six at the minimum supply voltage. Through some work function tuning, the cell sigma yields of the other structures reach above six for both read and write while being still lower than those of the proposed structure. [ABSTRACT FROM AUTHOR]