Enhanced Remnant Polarization (30 μC/cm2) and Retention of Ferroelectric Hf0.5Zr0.5O2 by NH3 Plasma Treatment

In this letter, NH 3 plasma treatment was utilized to improve the ferroelectric property of widely used TiN/Hf x Zr y O 2 (HZO)/TiN capacitors. The developed metal-ferroelectric-metal (MFM) structure shows high remnant polarization (P r ) of 30 ~\mu \text{C} /cm 2 after 10-min NH 3 treatment at bottom TiN electrode. Materials characterization were subject to investigate the behind mechanism. A higher ferroelectric o-phase formation in NH 3 -treated HZO device is revealed by grazing incidence X-ray diffraction (GIXRD). In addition, the high-resolution transmission electron microscopy (HRTEM) indicates that the NH 3 treatment optimizes the interface quality by restraining of the interfacial layer (IL) including intrinsic TiO x N y dead-layer and non-ferroelectric layer. Furthermore, the improved interface engineering also suppressed the imprint effect, which prompts the retention improvement of TiN/Hf x Zr y O 2 /TiN ferroelectric capacitors.