Effects of HfO₂ buffer layer thickness on the properties of Pt/SrBi₂Ta₂ O₉/HfO₂/Si structure

We investigated structural and characteristic changes in thin HfO₂ films (<10 nm) by varying their thicknesses and also examined their influence on the properties of Pt/SrBi₂ Ta₂O₉/Hfo₂/Si metal/ feffoelectric/insulator/semiconductor (MFIS) structures. HfO₂ films with different thicknesses were found to exhibit rather distinct characteristics and to profoundly affect the properties of the fabricated MFIS capacitor. We found that, when employing 3.2-nm-thick HfO₂ as the buffer layer, the MFIS capacitor showed good memory performance at low operation voltage. However, this study demonstrated that some of the HfO₂ limited its application in MFIS memory, even though it is the most promising alternative gate dielectric material.