Structural and thermoelectric characterization of individual single-crystalline nanowires

单个单晶纳米线的结构和热电表征

• 批准号: 122186230
• 负责人: Professorin Dr. Saskia F. Fischer
• 金额: --
• 依托单位: Institut für Metallische Werkstoffe
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2009
• 资助国家: 德国
• 起止时间: 2008-12-31 至 2015-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/122186230?language=en
• 关键词: Structural; thermoelectric; characterization; individual; single

The thermoelectric transport of semiconductor nanowires based on V-VI materials (Sb2Te3, Bi2Te3 and related ternary alloys) and one IV-VI material (PbTe) as a reference for high temperature measurements will be investigated. By engineering the doping level and surface morphology during and after the nanowire growth, bulk-like power factors and reduced thermal conductivities in comparison to the bulk counterparts should be achieved. The core of the project development is a measurement platform with integrated heaters and electrodes for advanced measurements and spatial manipulation of nanowires (NWs). This device is based on MEMS technology, which can be applied for low-temperature measurements and investigations in transmission electron microscopes (TEM). The individual nanowire will be placed on the MEMS platform. The electrical connection between the NWs and the platform is made in a last step, with a focus on developing a method which does not need any further microfabrication steps. Systematic measurements of the thermal conductivity as function of the nanowire diameter and the surface morphologies and structures will be carried out. Full ZT-characterization from 2 to 673 K will be performed with the thermoelectric characterization platform. Furthermore, the charge carrier mobility and density of gated nanowires at low temperature will be determined. The project goal will be a data correlation between the thermoelectric measurements, theoretic calculations, advanced chemical and TEM analysis from single nanowires and accompanying studies on the thermal stability of Bi2Te3/Sb2Te3 based nanostructures by tight collaborations within the SPP.

以V-VI材料（Sb2Te3、Bi2Te3及相关三元合金）和一种IV-VI材料（PbTe）作为高温测量参考，研究了半导体纳米线的热电输运。通过在纳米线生长过程中和之后设计掺杂水平和表面形态，可以实现与块体类似的功率因数和更低的热导率。项目开发的核心是集成加热器和电极的测量平台，用于纳米线（NWs）的高级测量和空间操作。该装置基于MEMS技术，可用于透射电子显微镜（TEM）的低温测量和研究。单个纳米线将放置在MEMS平台上。NWs和平台之间的电气连接是最后一步，重点是开发一种不需要进一步微加工步骤的方法。系统测量热导率作为纳米线直径和表面形貌和结构的函数将进行。从2到673 K的完整zt表征将使用热电表征平台进行。此外，还将测定门控纳米线在低温下的载流子迁移率和密度。该项目的目标是通过SPP内部的紧密合作，将单根纳米线的热电测量、理论计算、先进化学和TEM分析以及Bi2Te3/Sb2Te3纳米结构的热稳定性研究之间的数据关联起来。