Morphotropic Phase Boundary-Enhanced Polarization and High-Temperature Retention in Ferroeletric FET

In this study, we report a morphotropic phase boundary (MPB) with a peculiar design with a superlattice <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Hfo.25Zr0.75O2/HZO</tex> thickness ratio of 1:2.3. Different from classical HZO with κ~40, this MPB exhibits a superior κ value of 50. The MPB-based ferroelectric transistor (MPB-FeFET) is able to operate at half the read/write voltage and achieve three times the on-current compared to traditional ferroelectrics. To understand this peculiar phenomenon, we conducted quasi-static capacitance voltage (QSCV) measurement on the FeFET to extract P-V curves, ensuring that the endurance cycling exceeds <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">10¹</tex> cycles. Moreover, the superior high-κ effect of MPB also assists the heat transfer, exhibiting excellent high-temperature retention for up to 10 years at 106°C. This paves the way for future AIoT applications on the edge devices.