Crystallization annealing is a crucial process for the formation of the ferroelectric phase in HfO_(2)-based ferroelectric thin films.Here,we systematically investigate the impact of the annealing process,with tempera...Crystallization annealing is a crucial process for the formation of the ferroelectric phase in HfO_(2)-based ferroelectric thin films.Here,we systematically investigate the impact of the annealing process,with temperature varied from 350℃to 550℃,on the electricity,ferroelectricity and reliability of a Hf_(0.5)Zr_(0.5)O_(2)(HZO;7.5 nm)film capacitor.It was found that HZO film annealed at a low temperature of 400℃can effectively suppress the formation of the monoclinic phase and reduce the leakage current.HZO film annealed at 400℃also exhibits better ferroelectric properties than those annealed at 350℃and 550℃.Specifically,the 400℃-annealed HZO film shows an outstanding 2Pr value of 54.6μC·cm^(-2)at±3.0 MV·cm^(-1),which is relatively high compared with previously reported values for HZO film under the same electric field and annealing temperature.When the applied electric field increases to±5.0 MV·cm^(-1),the 2Pr value can reach a maximum of 69.6μC·cm^(-2).In addition,the HZO films annealed at 400℃and 550℃can endure up to bout 2.3×10^(8)cycles under a cycling field of 2.0 MV·cm^(-1)before the occurrence of breakdown.In the 400℃-annealed HZO film,72.1%of the initial polarization is maintained while only 44.9%is maintained in the 550℃-annealed HZO film.Our work demonstrates that HZO film with a low crystallization temperature(400℃)has quite a high ferroelectric polarization,which is of significant importance in applications in ferroelectric memory and negative capacitance transistors.展开更多
基金Hainan Provincial Natural Science Foundation of China(Grant No.523QN257)Collegelevel Scientific Research Foundation of Qiongtai Normal University(Grant No.qtqn202215)+6 种基金the Innovation and Entrepreneurship Training Program for College Students(Grant No.202213811016)Science and Technology Program of Henan(Grant No.232102210182)Scientific Research Foundation of Henan Normal University(Grant No.20230196)Natural Science Foundation of Shandong Province(Grant No.ZR2023QA047)Foundation of PeiXin(Grant No.2023PX027)Science and technology smes innovation ability improvement project(Grant No.2023TSGC0154)the National Natural Science Foundation of China(Grant No.62174059)。
文摘Crystallization annealing is a crucial process for the formation of the ferroelectric phase in HfO_(2)-based ferroelectric thin films.Here,we systematically investigate the impact of the annealing process,with temperature varied from 350℃to 550℃,on the electricity,ferroelectricity and reliability of a Hf_(0.5)Zr_(0.5)O_(2)(HZO;7.5 nm)film capacitor.It was found that HZO film annealed at a low temperature of 400℃can effectively suppress the formation of the monoclinic phase and reduce the leakage current.HZO film annealed at 400℃also exhibits better ferroelectric properties than those annealed at 350℃and 550℃.Specifically,the 400℃-annealed HZO film shows an outstanding 2Pr value of 54.6μC·cm^(-2)at±3.0 MV·cm^(-1),which is relatively high compared with previously reported values for HZO film under the same electric field and annealing temperature.When the applied electric field increases to±5.0 MV·cm^(-1),the 2Pr value can reach a maximum of 69.6μC·cm^(-2).In addition,the HZO films annealed at 400℃and 550℃can endure up to bout 2.3×10^(8)cycles under a cycling field of 2.0 MV·cm^(-1)before the occurrence of breakdown.In the 400℃-annealed HZO film,72.1%of the initial polarization is maintained while only 44.9%is maintained in the 550℃-annealed HZO film.Our work demonstrates that HZO film with a low crystallization temperature(400℃)has quite a high ferroelectric polarization,which is of significant importance in applications in ferroelectric memory and negative capacitance transistors.
