Sub‐Thermionic Negative Capacitance Field Effect Transistors with Solution Combustion‐Derived Hf<sub>0.5</sub>Zr<sub>0.5</sub>O<sub>2</sub>
Pavan Pujar, Haewon Cho, Srinivas Gandla, Muhammad Naqi, Seongin Hong, Sunkook Kim
Abstract
Abstract The fabrication of Hf 0.5 Zr 0.5 O 2 ‐ferroelectric negative capacitor using solution combustion is presented for the first time. The starting materials used for the solution combustion to form equimolar Hf 0.5 Zr 0.5 O 2 are to act as both combustible elements and cation sources. Jain's method, which is used for estimating the stoichiometric quantities of precursors in propellant chemistry, has also been modified and applied. The conventional assumption for this method that molecular oxygen does not take part in the reaction is refuted and stoichiometric combustion in the presence of molecular oxygen is proposed. This reaction is followed by post‐rapid thermal processing to stabilize the metastable, non‐centrosymmetric orthorhombic phase. The thin film stacks, Hf 0.5 Zr 0.5 O 2 /HfO 2 , are used to achieve sub‐thermionic swing (forward sweep: 25.42 ± 8.05 mV dec −1 , reverse sweep: 42.56 ± 4.87 mV dec −1 ) in MoS 2 negative capacitance field effect transistors with a hysteresis of ≈ 40 mV at 1 nA, resulting in ultra‐low‐power operation.