Summary: | We have demonstrated the method of threshold voltage (V<sub>T</sub>) adjustment by controlling Ge content in the SiGe p-channel of N1 complementary field-effect transistor (CFET) for conquering the work function metal (WFM) filling issue on highly scaled MOSFET. Single WFM shared gate N1 CFET was used to study and emphasize the V<sub>T</sub> tunability of the proposed Ge content method. The result reveals that the Ge mole fraction influences V<sub>TP</sub> of 5 mV/Ge%, and a close result can also be obtained from the energy band configuration of Si<sub>1-x</sub>Ge<sub>x</sub>. Additionally, the single WFM shared gate N1 CFET inverter with V<sub>T</sub> adjusted by the Ge content method presents a well-designed voltage transfer curve, and its inverter transient response is also presented. Furthermore, the designed CFET inverter is used to construct a well-behaved 6T-SRAM with a large SNM of ~120 mV at V<sub>DD</sub> of 0.5 V.
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