Enhanced Remnant Polarization (30 <i>μ</i>C/cm<sup>2</sup>) and Retention of Ferroelectric Hf<sub>0.5</sub>Zr<sub>0.5</sub>O<sub>2</sub> by NH<sub>3</sub> Plasma Treatment
Peng Yuan, Boping Wang, Yang Yang, Shuxian Lv, Yuan Wang, Yannan Xu, Pengfei Jiang, Yuting Chen, Zhiwei Dang, Yaxin Ding, Tiancheng Gong, Qing Luo
Abstract
In this letter, NH <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> plasma treatment was utilized to improve the ferroelectric property of widely used TiN/Hf <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">x</sub> Zr <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">y</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> (HZO)/TiN capacitors. The developed metal-ferroelectric-metal (MFM) structure shows high remnant polarization (P <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">r</sub> ) of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$30 ~\mu \text{C}$ </tex-math></inline-formula> /cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> after 10-min NH <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> treatment at bottom TiN electrode. Materials characterization were subject to investigate the behind mechanism. A higher ferroelectric o-phase formation in NH <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> -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 <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> treatment optimizes the interface quality by restraining of the interfacial layer (IL) including intrinsic TiO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">x</sub> N <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">y</sub> dead-layer and non-ferroelectric layer. Furthermore, the improved interface engineering also suppressed the imprint effect, which prompts the retention improvement of TiN/Hf <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">x</sub> Zr <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">y</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> /TiN ferroelectric capacitors.