Microscopic mechanism of imprint in hafnium oxide-based ferroelectrics  

作　　者：Peng Yuan Ge-Qi Mao Yan Cheng Kan-Hao Xue Yunzhe Zheng Yang Yang Pengfei Jiang Yannan Xu Yuan Wang Yuhao Wang Yaxin Ding Yuting Chen Zhiwei Dang Lu Tai Tiancheng Gong Qing Luo Xiangshui Miao Qi Liu 

机构地区：[1]Key Laboratory of Microelectronic Devices and Integrated Technology,Institute of Microelectronics,Chinese Academy of Sciences,No.3,Beitucheng West Road,Beijing 100029,China [2]University of Chinese Academy of Sciences,19 Yuquan Road,Beijing 100049,China [3]School of Integrated Circuits,School of Optical and Electronic Information,Huazhong University of Science and Technology,1037 Luoyu Road,Wuhan 430074,China [4]Key Laboratory of Polar Materials and Devices(MOE),Department of Electronics,East China Normal University,100 Guilin Road,Shanghai 430079,China [5]Department of Mathematics and Theories,Peng Cheng Laboratory,No.2,Xingke 1st Street,Shenzhen 518055,China

出　　处：《Nano Research》2022年第4期3667-3674,共8页纳米研究（英文版）

基　　金：This work was supported in part by the the National Natural Science Foundation of China(Nos.61974049,61922083,61804167,61834009,61904200,61821091,and 92064003);in part by the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB44000000).

摘　　要：Hafnia-based ferroelectrics have greatly revived the field of ferroelectric memory(FeRAM),but certain reliability issues must be satisfactorily resolved before they can be widely applied in commercial memories.In particular,the imprint phenomenon severely jeopardizes the read-out reliability in hafnia-based ferroelectric capacitors,but its origin remains unclear,which hinders the development of its recovery schemes.In this work,we have systematically investigated the imprint mechanism in TiN/Hf_(0.5)Zr_(0.5)O_(2)(HZO)/TiN ferroelectric capacitors using experiments and first-principles calculations.It is shown that carrier injection-induced charged oxygen vacancies are at the heart of imprint in HZO,where other mechanisms such as domain pinning and dead layer are less important.An imprint model based on electron de-trapping from oxygen vacancy sites has been proposed that can satisfactorily explain several experimental facts such as the strong asymmetric imprint,leakage current variation,and so forth.Based on this model,an effective imprint recovery method has been proposed,which utilizes unipolar rather than bipolar voltage inputs.The remarkable recovery performances demonstrate the prospect of improved device reliability in hafnia-based FeRAM devices.

关 键 词：hafnia-based ferroelectric IMPRINT build-in electric field oxygen vacancy recovery 

分 类 号：TM2[一般工业技术—材料科学与工程]