Measurement of Ferroelectric Properties of Nanometer Scaled Individual Metal/Hf_0.5Zr_0.5O₂/Metal Capacitors

Ferroelectric properties of individual TiN/Hf0.5Zr0.5O2/TiN capacitors have been measured for technologically relevant areas as small as 60 nm$\times70$nm, using direct detection of ultralow charge. A crossbar architecture has been utilized to fabricate the ferroelectric capacitors. Switching polarization of$40.1 \mu \text{C}$/cm$^{2} \ge \text{P}_{\text{sw}} \ge 16.7 \mu \text{C}$/cm2and coercive field 1.4 MV/cm$\ge \text{E}_{c} \ge1.09$MV/cm have been observed for sizes between$1.1 \mu \text{m}$2and 4200 nm2without discernable trend as function of capacitor size in the present data set. Measured bipolar stress endurance exceeds the maximum measured cycles of 1010although some capacitors start to show signs of degradation after 109cycles. A clear correlation between Pswdegradation and increased leakage current is observed. The direct measurement of such small area capacitors has been enabled by equipment and circuit design innovations. The present setup allows direct measurement of ferroelectric properties for capacitors as small as 1900 nm2while further improvements could extend the size limit to 950 nm2where the design window appears to close.