Kovařík Martin, Citterberg Daniel, Paiva de Araújo Estácio, Šikola Tomáš, Kolíbal Miroslav
CEITEC, Brno University of Technology, Purkyňova 123, 61200 Brno, Czech Republic.
Faculty of Mechanical Engineering, Institute of Physical Engineering, Brno University of Technology, Technická 2896/2, 616 69 Brno, Czech Republic.
ACS Appl Electron Mater. 2024 Dec 13;6(12):8776-8782. doi: 10.1021/acsaelm.4c01450. eCollection 2024 Dec 24.
To satisfy the needs of the current technological world that demands high performance and efficiency, a deep understanding of the whole fabrication process of electronic devices based on low-dimensional materials is necessary for rapid prototyping of devices. The fabrication processes of such nanoscale devices often include exposure to an electron beam. A field effect transistor (FET) is a core device in current computation technology, and FET configuration is also commonly used for extraction of electronic properties of low-dimensional materials. In this experimental study, we analyze the effect of electron beam exposure on electrical properties of individual WS nanotubes in the FET configuration by in-operando transport measurements inside a scanning electron microscope. Upon exposure to the electron beam, we observed a significant change in the resistance of individual substrate-supported nanotubes (by a factor of 2 to 14) that was generally irreversible. The resistance of each nanotube did not return to its original state even after keeping it under ambient conditions for hours to days. Furthermore, we employed Kelvin probe force microscopy to monitor surface potential and identified that substrate charging is the primary cause of changes in nanotubes' resistance. Hence, extra care should be taken when analyzing nanostructures in contact with insulating oxides that are subject to electron exposure during or after fabrication.
为满足当前对高性能和高效率有要求的技术世界的需求，对于基于低维材料的电子器件进行快速原型制作而言，深入了解其整个制造过程是必要的。此类纳米级器件的制造过程通常包括电子束曝光。场效应晶体管（FET）是当前计算技术中的核心器件，FET配置也常用于提取低维材料的电子特性。在本实验研究中，我们通过扫描电子显微镜内的原位输运测量，分析了电子束曝光对FET配置中单个WS纳米管电学性质的影响。在电子束曝光后，我们观察到单个衬底支撑纳米管的电阻发生了显著变化（变化因子为2至14），且这种变化通常是不可逆的。即使将每个纳米管在环境条件下放置数小时至数天，其电阻也不会恢复到原始状态。此外，我们采用开尔文探针力显微镜来监测表面电位，并确定衬底充电是纳米管电阻变化的主要原因。因此，在分析与绝缘氧化物接触且在制造期间或之后会受到电子曝光的纳米结构时，应格外小心。
