Piezotronic effects in freestanding microcomposites

在这个项目中，我们采用了一种利用压电效应开发高灵敏度磁场传感器的新方法。除了对磁电（ME）传感器的压电概念的基本理解外，与当前状态相比，灵敏度显着增加。传感器由磁致伸缩元件和压电元件组成的自由站立复合结构组成。高纵横比的一维ZnO微纳米结构将被采用，因为他们对这些材料的支持具有丰富的经验。为了使定制设计的氧化锌晶体满足压电应用的要求，一种新的火焰传输合成将被使用。由于压电特性对形貌、缺陷、晶体质量、界面和局部变形行为的强烈依赖，需要在不同长度尺度范围内对这些结构特性进行精确的了解。申请人之间在晶体生长和电子显微镜和微x射线衍射原位表征领域的现有协同作用将在本项目中建立。这些互补的表征方法一起提供了以从微米到纳米到原子长度尺度的最高精度进行空间分辨结构分析的可能性。极具挑战性的方面是原位电子显微镜和operando x射线散射实验的计划方法开发。由于结构、电子和电气特性的并行特性，将有可能设计出压电偏置质谱传感器，提供以前无法实现的高灵敏度。在这个项目中获得的理解将为知识转移到其他系统（如AIN偏置ME传感器）提供基础。

In this project, we adopt a new approach to developing highly sensitive magnetic field sensors via piezotronic effects. In addition to a fundamental understanding of piezotronic concepts for magnetoelectric (ME) sensors a significant increase in sensitivity as compared to the current status. The sensors consist of freely standing composite structures consisting of a magnetostrictive and a piezoelectric component. One dimensional ZnO micro- and nanostructures with high aspect ratios will be employed due to their extensive experience of the proponents with these materials. In order to allow custom design of ZnO crystals meeting the requirements for piezotronic applications a new flame transport synthesis will be used. Due to the strong dependence of piezotronic properties on morphology, defects, crystal quality, interfaces, and local deformation behaviour an exact knowledge of these structural properties on a range of different length scales is required. The existing synergy between the applicants in the area of crystal growth and in situ characterisation by electron microscopy and micro X-ray diffraction will be built upon in this project. These complimentary characterisation methods together provide the possibility to perform spatially resolved structural analysis with the highest precision from the micron through nanometre down to atomic length scales. Highly challenging aspects are the planned method development for in situ electron microscope and operando X-ray scattering experiments. Due to the parallel characterisation of structural, electronic, and electrical properties it will be possible to engineer piezotronic biased MS sensors delivering previously unattainable high levels of sensitivity. The understanding obtained in this project will provide a foundation for knowledge transfer to other systems such as AIN biased ME sensors.