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Impact of Mole Fractions due to Work Function Variability (WFV) of Metal Gate on Electrical Parameters in Strained SOI-FinFET

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In the recent sub-20 nm technology node, the process variability issues have become a major problem for scaling of MOS devices. We present a design for a strained Si/SiGe FinFET on an insulator using a 3D TCAD simulator. The impact of metal gate work function variability (WFV) on electrical parameters is studied. Such impact of WFV for different mole fractions (x) of the SiGe layer in a strained SOI-FinFET with varying grain size is presented. The results show that as the mole fraction is increased, the variability in threshold voltage (σVT) and off current (σIoff) is decreased; while, the variability of on-current (σIon) is increased. A notable observation is the distribution of electrical parameters approaches a normal distribution for smaller grain sizes.

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The authors acknowledge the funding by Council of Scientific and Industrial Research, Govt. of India (CSIR Sanction Reference. No. 22(0737)/17/EMR-II).

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Correspondence to Rajesh Saha.

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Saha, R., Bhowmick, B. & Baishya, S. Impact of Mole Fractions due to Work Function Variability (WFV) of Metal Gate on Electrical Parameters in Strained SOI-FinFET. Silicon 12, 577–583 (2020).

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  • Grain orientation
  • Metal gate granularity
  • Mole fraction
  • Strained SOI-FinFET
  • Work function variability