Performance Assessment of Nanoscale SiGe High-k Negative Capacitance Junctionless GAA MOSFETs

Our approach in this paper aims at investigating the impact of combining high-k dielectric materials with ferroelectric materials on the performance of silicon-germanium (SiGe) Junctionless Gate-All-Around (GAA) Field-Effect Transistors (SiGe-High-k-NCJLGAA-FETs). This offers unique advantage and can lead to a significant improvement in the device performance. The combination of high-k dielectrics and ferroelectric materials enhances the device electrical properties by providing enhanced channel electrostatic behavior. The electrical performance of the considered device (SiGe-High-k-NCJLGAA-FETs) is investigated by developing combined analytical and numerical models using ATLAS 2D simulator. The surface potential and subthreshold swing models, including short channel are developed by solving the Landau-Khalatnikov (L-K) equation with Poisson's equation. The effect of the Ge mole fraction on the device electrical performance is investigated. In addition, the influence of various high-k dielectric materials on the device performance is analyzed. A minimum swing factor (SS) of 31.2 mV/decade is recorded for L=30 nm using the doped-hafnium oxide as ferroelectric material and SiGe channel with TiO<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> gate oxide. These enhancements make the optimized transistor device highly approriate for usage in low-power and digital nanoelectronic applications.