A Novel Metal-Ferroelectric-Insulator-Silicon FET With Selectively Nucleated Lateral Crystallized Pb(Zr,Ti)O3 and ZrTiO4 Buffer for Long Retention and Good Fatigue

A novel metal-ferroelectric-insulator-silicon (MFIS) field-effect transistor (FET) with a Pt/Pb(Zr,Ti)O₃ (PZT)/ ZrTiO₄ (ZTO)/p-Si structure was fabricated and investigated for the first time. The PZT was formed by selectively nucleated lateral crystallization (SNLC), showing large rectangularlike grains (~40 μm) and smooth interface properties. An ultrathin ZTO layer showed a high dielectric constant (50), smooth interfaces in a ZTO/p-Si and PZT/ZTO layer, and an excellent interdiffusion barrier. From these material properties, the MFIS FET showed an excellent fatigue characteristic, which did not show any degradation in memory window (2.1 V), gate current density (10^-8 A/μm), and fast P/E switching speed (500 ns) even after 10¹¹ fatigue cycles. Furthermore, a long retention time, which only decreased 12.55% after 1 month and 26.97% after 10 years, was exhibited.