Negative Capacitance in Short-Channel FinFETs Externally Connected to an Epitaxial Ferroelectric Capacitor
Khan, A.I., K. Chatterjee, J.P. Duarte, Z. Lu, A. Sachid, S. Khandelwal, Ramamoorthy Ramesh, C. Hu, S. Salahuddin
We report subthreshold swings as low as 8.5 mV/decade over as high as eight orders of magnitude of drain current in short-channel negative capacitance FinFETs (NC-FinFETs) with gate length Lg=100 nm. NC-FinFETs are constructed by connecting a high-quality epitaxial bismuth ferrite (BiFeO3) ferroelectric capacitor to the gate terminal of both n-type and p-type FinFETs. We show that a self-consistent simulation scheme based on Berkeley SPICE Insulated-Gate-FET Model:Common Multi Gate model and Landau-Devonshire formalism could quantitatively match the experimental NC-FinFET transfer characteristics. This also allows a general procedure to extract the effective S-shaped ferroelectric charge-voltage characteristics that provides important insights into the device operation. © 2015 IEEE.
IEEE Electron Device Letters
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