Effect of Scandium Insertion Into the Gate-Stack of Ferroelectric Field-Effect Transistors

We demonstrated improved switching voltage and retention and endurance characteristics in HfZrOx (HZO)-based ferroelectric field-effect transistors (FeFETs) via oxygen scavenging with Sc. Insertion of Sc into the gate-stack successfully reduced the thickness of the interfacial SiOx layer (IL) between HZO and Si; thus, the FeFET with Sc could perform an immediate read-after-write at a 2-V pulse. In addition, although the IL thickness became thinner, the endurance characteristics of FeFETs with Sc were improved up to
$10^{{10}}$
cycles, due to the lower
${V}_{g}$
required for the same memory window (MW) and less trapping when positive pulses are applied. We believe that this work contributes to the low-voltage operation of FeFET and proposes the potential of oxygen scavenging.