Demonstration of EOT-Scaled Lg∼25 nm FinFET Based on Thickness-Proportion Controlled HfO ₂ -ZrO ₂ -HfO ₂ Superlattice Gate Stacks

We demonstrate the equivalent oxide thickness (EOT)-scaled FinFETs with a physical gate length <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$(L_{\mathrm{g}})$</tex> of <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\sim 25$</tex> nm based on a thickness-proportional controlled <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\text{HfO}_{2}-\text{ZrO}_{2}- \text{HfO}_{2}$</tex> (TPC-HZH) superlattice gate stacks. The integrated gate oxides show an effective oxide thickness (EOT) of 7 Å after <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$450^{\circ}\mathrm{C}$</tex> annealing, indicating high compatibility with advanced HKMG FinFETs processes. Superior performance from the low EOT sustains on the <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$L_{\mathrm{g}}\sim 25$</tex> nm TPC-HZH FinFET, showing a 38% higher driving current and a 54% higher transconductance compared with that of traditional <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\text{HfO}_{2}$</tex>. based FinFET. Besides, enhanced SCE immunity, including SS and DIBL, of the TPC-HZH, indicates the great potential of TPC-HZH capability for future advanced node CMOS technology.