Record-high 2P r =60 μC/cm 2 by Sub-5ns Switching Pulse in Ferroelectric Lanthanum-doped HfO 2 with Large Single Grain of Orthorhombic Phase >38 nm

In this work, we fabricate and characterize La-doped HfO2ferroelectric capacitors to significantly improve the short pulse switching performance of hafnium-based ferroelectric technology. Systematic study of side-by-side comparison of typical Hf0.5Zr$_{0.5} O_{2}$(HZO) and La-doped HfO2(HfLaO) are carried out in terms of material properties, polarization switching using P-V loop and ultrafast pulse measurement, showing significant improvement of the HfLaO device. Single grain over 38 nm of orthorhombic phase in HfLaO is observed by TEM, providing a material basis for excellent ferroelectric switching. Large $2P_{r} = 63.4 \mu C /cm^{2}$ and record high current density over 2.5 A/cm2per kHz in the HfLaO device has been demonstrated using P-V loop measurement. Furthermore, record-high $2P_{r} = 60 \mu C /$cm2is achieved under a very short pulse of 5 ns, twice higher than the previous record. A new parameter “switching conductivity G” is proposed to reflect the effectiveness of polarization switching. Record-high, voltage-independent $G= 1.03 \times 10^{4}S /$cm2has been obtained in our HfLaO devices owing to the large grain size with uniform switching properties.