Silicon-doped hafnium oxide anti-ferroelectric thin films for energy storage

• Published in: Journal of applied physics Vol. 122; no. 14
• Main Authors: Ali, Faizan, Liu, Xiaohua, Zhou, Dayu, Yang, Xirui, Xu, Jin, Schenk, Tony, Müller, Johannes, Schroeder, Uwe, Cao, Fei, Dong, Xianlin
• Format: Journal Article
• Language: English
• Published: Melville American Institute of Physics 14.10.2017
• Subjects: Aluminum oxide; Antiferroelectricity; Applied physics; Electronic devices; Electrostatic discharges; Endurance; Energy; Energy storage; Ferroelectric materials; Hafnium oxide; Induced polarization; Silicon; Thermal stability; Thin films
• DOI: 10.1063/1.4989908
• ISSN: 0021-8979

Motivated by the development of ultracompact electronic devices as miniaturized energy autonomous systems, great research efforts have been expended in recent years to develop various types of nano-structural energy storage components. The electrostatic capacitors characterized by high power density are competitive; however, their implementation in practical devices is limited by the low intrinsic energy storage density (ESD) of linear dielectrics like Al2O3. In this work, a detailed experimental investigation of energy storage properties is presented for 10 nm thick silicon-doped hafnium oxide anti-ferroelectric thin films. Owing to high field induced polarization and slim double hysteresis, an extremely large ESD value of 61.2 J/cm3 is achieved at 4.5 MV/cm with a high efficiency of ∼65%. In addition, the ESD and the efficiency exhibit robust thermal stability in 210–400 K temperature range and an excellent endurance up to 109 times of charge/discharge cycling at a very high electric field of 4.0 MV/cm. The superior energy storage performance together with mature technology of integration into 3-D arrays suggests great promise for this recently discovered anti-ferroelectric material to replace the currently adopted Al2O3 in fabrication of nano-structural supercapacitors.