Coupling between Piezoelectricity and Charge Transport Property in ZnO Nanowires

该奖项是根据2009年美国复苏和再投资法案（公法111-5）资助的。技术：本项目的目的是研究和理解ZnO一维纳米结构中压电电位和电荷输运行为之间相互作用的基本现象。本研究旨在(1)将ZnO纳米线中压电电位的强度和分布与ZnO纳米线的尺寸、应变和载流子密度联系起来，揭示自由电荷屏蔽对压电性的影响；(2)研究ZnO纳米线沟道上的压电场如何调节载流子迁移率；(3)建立载流子迁移率与纳米线的基本物理性质（包括尺寸、应变和载流子密度）之间的一般关系。合成了具有矩形截面的氧化锌纳米线，并将其用于压电和电学表征。该研究还计划使用ZnO纳米线制造压电门控晶体管，并对这些晶体管进行研究，以验证该项目建立的理论框架。非技术：该项目涉及材料科学主题领域的基础研究问题，具有高技术相关性。该研究的成功有望为压电半导体纳米材料在先进传感和能量收集纳米器件中的应用奠定基础。该项目的研究部分与PI的纳米材料和纳米技术研究生课程和陶瓷本科课程相结合。该项目还为培养纳米科学前沿制造和表征技术的研究生和本科生提供了极好的机会。

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).Technical: The objective of this project is to study and understand fundamental phenomena underlying the interaction between the piezoelectric potential and charge transport behavior in ZnO one-dimensional nanostructures. The research aims to (1) correlate the intensity and distribution of piezoelectric potential in a ZnO nanowire with the size, strain and carrier density and to reveal the free charge screening effect on the piezoelectricity; (2) investigate how the carrier mobility is regulated by the piezoelectric field across a ZnO nanowire channel; (3) establish a general relationship between the carrier mobility and the nanowire's basic physical properties, including size, strain and carrier density. Zinc oxide nanowires with a rectangular cross section are synthesized and used for the piezoelectric and electric characterization. The research also plans to fabricate piezoelectricity-gated transistors using ZnO nanowires and to study these transistors in order to validate the theoretical framework established under this project. Non-technical: The project addresses basic research issues in a topical area of materials science with high technological relevance. The success of the research is expected to lay a foundation for applying piezoelectric semiconductor nanomaterials in advanced sensing and energy harvesting nanodevices. The research component of the project is integrated with the PI's new graduate course on Nanomaterials and Nanotechnology and an undergraduate course on Ceramics. The project also provides an excellent opportunity for training graduate and undergraduate students with fabrication and characterization technologies in the frontier of nanoscience.