Improved Ferroelectricity and Tunneling Electro Resistance in Zr-Rich Hf<sub>x</sub>Zr<sub>1-x</sub>O<sub>2</sub> Ferroelectric Tunnel Junction
Jiajie Yu, Tianyu Wang, Zhenhai Li, Yongkai Liu, Jialin Meng, Kang Xu, Pei Liu, Hao Zhu, Qingqing Sun, David Wei Zhang, Lin Chen
Abstract
HfO2 based ferroelectric materials have great application potential in ferroelectric tunneling junction. Here, the low temperature annealed Zr-Rich HfxZr <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$1_{-\text {x}}\text{O}_{{2}}$ </tex-math></inline-formula> films based ferroelectric tunnel junction is fabricated on a silicon substrate. It is found that ferroelectricity of the film under operating voltages of 3.3V, 3.5V and 3.7V are excellent, where the largest residual polarization 2Pr is above 50 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mu \text{C}$ </tex-math></inline-formula> /cm2. The excellent ferroelectricity enables the device to operate at an extremely high speed of 50ns and achieve a high tunneling electro resistance ratio (>50). Based on the first principal calculation, we found that Zr-Rich HfxZr1-xO2 films will show more O-phase and less T-phase. This research paves the pathway to improve the performance of the HfO2 based ferroelectric tunneling junction for future ferroelectric application.