高级检索
无机材料学报

无机材料学报

• •    

压电力显微镜表征Pb(Mg,Nb)O3-PbTiO3超薄膜弛豫特性

董晨雨1, 郑维杰1, 马一帆2, 郑春艳1, 温峥1,2   

  1. 青岛大学1.物理科学学院;
    2.电子信息学院,青岛 266071
  • 收稿日期:2024-11-09 修回日期:2025-01-19
  • 通讯作者: 温峥, 教授. E-mail: zwen@qdu.edu.cn
  • 作者简介:董晨雨(1999-), 女, 硕士研究生. E-mail: 18244065981@163.com
  • 基金资助:
    国家自然科学基金(52372113); 山东省泰山学者人才工程 (tstp20240511)

Piezoresponse Force Microscopy Characterizations on Relaxor Properties of Ultrathin Pb(Mg,Nb)O3-PbTiO3 Films

DONG Chenyu1, ZHENG Weijie1, MA Yifan2, ZHENG Chunyan1, WEN Zheng1,2   

  1. 1. College of Physics, Qingdao University, Qingdao 266071, China;
    2. College of Electronics and Information, Qingdao University, Qingdao 266071, China
  • Received:2024-11-09 Revised:2025-01-19
  • Contact: WEN Zheng, professor. E-mail: zwen@qdu.edu.cn
  • About author:DONG Chenyu (1999-), female, Master candidate. E-mail: 18244065981@163.com
  • Supported by:
    National Natural Science Foundation of China (Grants No. 52372113); Taishan Scholar Program of Shandong Province (tstp20240511)

PDF (PC)

20

摘要： 弛豫铁电体因其卓越的介电和压电特性,在传感器、光电器件、高密度存储器、类脑计算等领域展现出广泛的应用潜力。然而,纳米尺度超薄膜的弛豫特性研究受到严重漏电流的限制,基于Sawyer-tower电路和Positive-Up-Negative-Down(PUND)脉冲波形的测试方法存在显著挑战。本研究提出了一种基于压电力显微镜(Piezoresponse Force Microscopy, PFM)的测试方法,来研究纳米尺度弛豫薄膜的极化特性。以Pb(Mg,Nb)O3-PbTiO3 (PMN-PT)超薄膜为例,比较了不同厚度的PMN-PT弛豫薄膜与铁电Pb(Zr,Ti)O3薄膜在双频追踪PFM测量中On-field和Off-field两种模式下的极化回滞行为。通过调节PFM回线测量中的用于极化读出的交流信号电压振幅,系统表征了纳米厚度PMN-PT薄膜的弛豫特性。进一步对不同面内应变和厚度的PMN-PT超薄膜进行PFM测试,发现在较大压应变下,弛豫特性被抑制,表现出显著的铁电特性,并观测到铁电-弛豫转变的临界厚度。这些实验结果验证了所提出测试方法的有效性。本研究不仅为超薄膜弛豫特性的探索提供了一种新的表征方法,也为理解铁电材料的弛豫极化行为奠定了基础,推动了弛豫铁电材料在低维电子学器件中的应用。

关键词: 弛豫铁电体, 压电力显微镜, PMN-PT, 超薄膜, 极化特性

Abstract: Relaxor ferroelectrics exhibit extensive applications in sensing technology, optoelectronics, high-density memory storage, and neuromorphic computing, owing to their superior dielectric and piezoelectric characteristics. However, conventional methods, including the Sawyer-Tower circuit and the Positive-Up-Negative-Down pulse train, prove inadequate for nanoscale ultra-thin films, since the relaxor characteristics may be hindered by substantial leakage currents. In this study, we propose a piezoresponse force microscopy(PFM)-based method for characterizing the nanoscale relaxor properties. Taking ultra-thin Pb(Mg,Nb)O3-PbTiO3 (PMN-PT) films as examples, this work compares the polarization hysteresis behavior under On-field and Off-field modes of the Dual AC Resonance Tracking (DART) PFM measurements, between relaxor PMN-PT and ferroelectric Pb(Zr,Ti)O3 thin films with varying thicknesses. The relaxor characteristics of nanometer-thick PMN-PT films are characterized by modulating the amplitude of AC readout to eliminate potential false signals. Furthermore, PFM characterizations of PMN-PT ultra-thin films under different in-plane compressive strains and thickness demonstrate that the relaxor characteristics are suppressed and ferroelectric properties are observed at relatively large compressive strains of 3.19%. Additionally, the critical thickness for ferroelectric-relaxor transition is identified. These results verify the availability of the proposed PFM-based method for the characterization of nanoscale relaxor properties. Therefore, this study not only provides a novel characterization method for the exploration of the relaxor characteristics in ultra-thin films, but also establishes a foundation for the understanding of the relaxor polarization behavior in ferroelectric materials, thereby advancing the applications of relaxor ferroelectric materials in low-dimensional electronic devices.

Key words: relaxor ferroelectrics, PFM, PMN-PT, ultra-thin films, polarization properties