A 5-nm 135-Mb SRAM in EUV and High-Mobility Channel FinFET Technology With Metal Coupling and Charge-Sharing Write-Assist Circuitry Schemes for High-Density and Low-VMIN Applications

A 135-Mb 0.021- $\mu \text{m}^{2}$ 6-T high-density SRAM bit cell with write-assist circuitries was successfully implemented by using 5-nm HK-metal gate FinFET with EUV and high-mobility channel (HMC) technology. This article proposes the metal capacitor coupling negative bitline (NBL) and the charge-sharing lower cell-VDD (CS-LCV) write-assist techniques to reduce the SRAM minimal supply voltage. Flying bitline (FBL) architecture is also implemented to improve the high-density SRAM macro-bit density by 5%. Silicon data show that both NBL and LCV write-assist techniques can improve the overall SRAM minimal supply voltage performance by more than 300 mV at the 95th percentile.

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