柔性Pb(Zr_(0.53)Ti_(0.47))O_3薄膜的高温铁电特性

随着柔性电子产品的迅速发展,具有优异铁电和压电性的Pb(Zr_(0.53)Ti_(0.47))O_3 (PZT)薄膜在柔性的非易失性存储器、传感器和制动器等器件中有广泛的应用前景.同时,由于外部环境越来越复杂,具有高温稳定特性的材料和器件受到越来越多的关注.本文在耐高温的二维层状氟晶云母衬底上,用脉冲激光沉积技术制备出外延的PZT薄膜,并通过机械剥离的方法,得到柔性的外延PZT薄膜.研究了Pt/PZT/SRO异质结的铁电和压电性及其高温特性,发现样品表现出优越的铁电性,剩余极化强度(P_r)高达65μC/cm~2,在弯曲104次后其铁电性基本保持不变,且样品在275℃高温时仍然保持良好的铁电性.本文为柔性PZT薄膜在航空航天器件中的应用提供了实验基础.

Ferroelectricity of flexible Pb(Zr0.53Ti0.47)O3 thin film at high temperature

Recently, flexible electronic devices have attracted extensive attention due to their characteristics of flexibility, miniaturization and portability. Flexible functional oxide thin films with high performance and stability are the basis for high-performance flexible electronic devices. Perovskite lead zirconate titanate Pb(Zr_0.53Ti_0.47)O₃ (PZT) at "morphotropic phase boundary" indicates excellent ferroelectricity and piezoelectricity, and has broad prospects in flexible non-volatile memories, sensors and actuators. Moreover, high-temperature stable flexible memories and sensors have received increasing attention due to the escalating complexity of the external environment. In the present work, Pb(Zr_0.53Ti_0.47)O₃/SrRuO₃/BaTiO₃ (PZT/SRO/BTO) heterostructures are prepared by pulsed laser deposition on high temperature resistant two-dimensional layered fluorphlogopite mica substrates. Afterward, flexible epitaxial PZT thin films are obtained by mechanical stripping. The ferroelectricity, piezoelectricity and high temperature characteristics of PZT thin films are investigated. The thin films show superior ferroelectricity at room and high temperatures. At room temperature, the thin films exhibit excellent ferroelectricity with a remnant polarization (P_r) of~small$ {rm{65}};{text{μ}} {rm{C/c}}{{rm{m}}^{rm{2}}}$. A saturation polarization (P_s) of~$ {rm{80}};{text{μ}} {rm{C/c}}{{rm{m}}^{rm{2}}}$ and a coercive field (E_c) of~100 kV/cm are also observed. In addition, after bending the thin films to a 1.5 cm radius 10⁴ times, their ferroelectricity does not show deterioration at room temperature. In order to study the ferroelectricity of PZT thin films at high temperature, P-E loops from 27℃ to 275℃ are tested. The results show that the films still show excellent ferroelectricity with a P_r of~$ {rm{50}};{text{μ}} {rm{C/c}}{{rm{m}}^{rm{2}}}$ and a P_s of~$ {rm{70}};{text{μ}} {rm{C/c}}{{rm{m}}^{rm{2}}}$ at 275℃. The present work provides a basis for the application of flexible epitaxial PZT thin film. Especially, the ferroelectricity of flexible PZT thin films at high temperature provides a possibility of obtaining high-temperature flexible electronic devices.