Three-Orders Improvement of Endurance in Hafina Based MFS Capacitor through CF4 Plasma Pre-Treatment

In hafina ferroelectric based FeFET device, endurance issue is one of the most critical concern. In this work, an effective approach of $\text{CF}_{4}$ plasma pre-treatment on the Si surface before $\text{Hf}_{0.5}\text{Zr}_{0.5}\mathrm{O}_{2}$ deposition was employed to improve interface quality of metal-ferroelectric-semiconductor (MFS) capacitor, which is the key component of FeFET device. The F plasma pre-treatment was found helpful to reduce the leakage current and increase the breakdown voltage of MFS capacitor. In the sample treated with $\text{CF}_{4}$ plasma for 10 seconds, the endurance property of MFS capacitor was successfully enhanced to 108 cycles, which are 3 orders higher than the non-treated sample. Along with the improvement of endurance, the coercive field was also found increased 20 percent, which is beneficial to increase the memory window $(2\mathrm{E}_{\mathrm{c}})$ of FeFET. The observed phenomenon could be well understood by the improved interface quality and reduced leakage current.