Atomic Level Characterization of Organic Molecule-Semiconductor Heterostructures by High-resolution Soft Probes

通过高分辨率软探针对有机分子-半导体异质结构进行原子级表征

基本信息

批准号：
15201022
负责人：
NAGAO Tadaaki
金额：
$ 31.37万
依托单位：
National Institute for Materials Science (2004)Tohoku University (2003)
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (A)
财政年份：
2003
资助国家：
日本
起止时间：
2003 至 2004
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-15201022/
关键词：
Organic molecule Ultrathin film MBE Crystal growth STM Metal contact Low-energy electron III-V族化合物半導体

项目摘要

In this project, we aimed at elucidating the atomistic picture of the growth process of the organic thin films on semiconductor substrates to obtain useful knowledge for the fabrication of highquality organic thin films. Based on our experience and techniques for characterizing and controlling the epitaxial growth of various semiconductor-on-semiconductor and metal-on-semiconductor surfaces, we tried to extract new knowledge and guiding principles which should be useful for realizing high-quality organic molecular beam epitaxy '(OMBE). Conductive soft materials such as organic semiconductor on Si substrates has become more and more important these days as a promising building blocks for the next generation microelectronics devices. These soft materials are not suited to be studied by conventional surface-sensitive electron probes such as reflection high-energy electron diffraction (RHEED) and other microscopy techniques using electron beams or tunneling electrons. In this context, high … More -sensitivity soft probes without, or with extremely low electron dose has been strongly desired, In the present project, we utilize high-sensitivity soft probes with slow electron beam such as high-resolution electron energy loss spectroscopy (HREELS), spot-profile-analyzing low-energy electron diffraction (SPA LEED) and low-energy electron microscopy (LEEM) and non-contact atomic force microscopy (nc-AFM). These novel analytical tools are nondestructive against organic thin layers and provides us important information on the structural and functional properties of organic heterostructures. In this project, we have systematically searched for good inorganic substrates for the high-quality growth of pentacene overlayer, such as stepped silicon surfaces, high-index silicon surfaces, metal monolayer coated surfaces, etc. Substrates with metallic surfaces are concluded to be not suited for the formation of abrupt interfaces since the molecules lies down and mostly forms disordered wetting layer. The same happens for the insulating substrates such as silicon dioxide. The best system we found was the Bi multi layers on Si(111) -7x7 substrate, which has rather inert chemical nature against the molecule but still highly conductive due to its semimetallic electronic and bond nature. On this template surface, we have found that the pentacene growth perfectly epitaxially to the Si(111) substrate and its domain size ranges more than a few tens of micrometers. We have found various other organic molecules and several good combinations for the hetemepitaxial OMBE growth which will be suited to form p-n organic junction, electroluminescence device structure, etc. We judge our project as very successful one which provided new knowledge on the atomistic characterization and precise control of the OMBE and thus opens up a wide avenue towards the development of new low-dimensional functional materials for the future microelectronics device application. Less

在这个项目中，我们旨在阐明半导体基板上有机薄膜生长过程的原子图，以获取用于制造高质量有机薄膜的有用知识。基于我们表征和控制各种半导体 - 启发式导体和金属 - 偏头向导体表面的外延生长的经验和技术，我们试图提取新的知识和指导原理，这些原理应有助于实现高质量的有机分子束外观外观'（OMBE）。作为下一代微电子设备的承诺构建块，SI底物上的有机半导体等导电软材料（例如有机半导体）变得越来越重要。这些软材料不适用于使用传统的表面敏感电子探针进行研究，例如反射高能电子衍射（RHEED）和其他使用电子束或隧道电子电子的显微镜技术。在这种情况下，在本项目中强烈希望没有或以极低的电子剂量或极低的电子剂量，我们使用慢敏感的软问题（例如高分辨率电子损失光谱（HREELS），较低的柔软问题（HREELS），较低的柔软问题（HREELS），高敏感的柔软问题（HREELS），低调分析的低调电子差异（Spa Leed（Spa Leed（Spa Leed）），我们利用高敏感的柔软问题（spa leem and-necopro）（le-Elect and neerron（spa ly-norron），我们利用高敏感的软问题（le-nre-Elect（le-Encopro））原子力显微镜（NC-AFM）。这些新型的分析工具对有机薄层是无损的，并为我们提供了有关有机异质结构的结构和功能特性的重要信息。在这个项目中，我们系统地搜索了良好的无机底物，以供五苯覆盖剂的高质量增长，例如梯级硅表面，高索引硅表面，金属单层涂层表面等。与金属表面相关的底物不适合于均不适合降解的摩尔群落，因为它不适合降落的造成摩尔群的造成摩尔群落。层。绝缘底物（例如二氧化硅）也会发生同样的情况。我们发现的最好的系统是Si（111）-7x7底物上的BI多层，该层具有针对该分子的惰性化学性质，但由于其半金属电子和键的性质，其导电性仍然很高。在此模板表面上，我们发现五苯烯的生长完全上一行至SI（111）底物及其域大小范围范围超过几十微米。我们发现了多种有机分子和几种良好的组合，用于异发型OMBE增长，这些组合将适合形成P-N有机连接，电致发光设备的结构等。我们认为我们的项目是非常成功的项目，该项目提供了有关OMBE的原子特征和精确控制的新知识，并因此开发了较广泛的设备，从而开发了新的型号，以实现新的质量材料。较少的