Special Seminar: Atomic-scale Manipulation of Ferroic Order in CMOS Compatible thin films on Si

The critical size limit of electric polarization remains an open domain in nanoscale ferroelectric research; in particular, the fundamental limit of switchable electric dipoles has extensive implications for the scaling of energy-efficient nanoelectronics due to the intrinsic ability to control electric polarization with an applied voltage. As ferroelectric materials are made thinner however, polarization is typically suppressed, as size effects in ferroelectrics have been thoroughly investigated in the prototypical perovskite oxides. Furthermore, perovskites suffer from various chemical, thermal, electrical, and interfacial incompatibilities with silicon and modern semiconductor processes. However, fluorite-structure binary oxides have attracted considerable interest as they overcome many of the silicon compatibility issues afflicting its perovskite ferroelectric counterparts. In this talk I shall discuss how our group and I have addressed the missing void in ferroelectric research regarding ultrathin stabilization and Si as well as GaN compatibility and demonstrated its application in stabilizing negative capacitance – a novel phenomenon present in ferroelectric materials which enables energy-efficient nanoscale transistors, furthermore, its application for on-chip energy storage with several orders faster than commercial Li-ion micro-batteries, a breakthrough in power-electronics. I will also discuss first of its kind reversible light-induced ferroelectricity in 1.5 nm thin film directly grown on silicon.