Interfaces in Organic Thin Film Transistors

本提案的目标是通过对现有和新型有机/无机和有机/有机结构的详细界面分析，实现对有机基薄膜晶体管（OTFT）发展的基本理解。该方法是详细探测模型OTFT结构/器件中的界面特性。注意力将集中在电子结构，化学反应，相互扩散和电荷转移的有机/金属，有机/有机和有机/介电界面从微观或原子的观点。界面分析将与OTFT的形态和基本电学特性相协调。我们的目标是提供一个更好的理解的有机半导体的界面特性的基本方面，并将此接口的知识，下一代OTFT。表面/界面分析工具包括X射线光电子能谱（XPS）、紫外光电子能谱（UPS）、逆光电子能谱（IPES）、近边X射线吸收精细结构（NEXAFS）和低能电子衍射（LEED）。界面/表面分析将得到结构和电子表征的支持，包括原子力显微镜（AFM）、扫描电容-电压（SCV）、扫描隧道显微镜（STM）和扫描隧道光谱（STS）。分析还将补充器件表征，包括基本电气表征、内部光发射和电吸收。在超高真空（UHV）环境中，通过受控气相沉积和原位溅射，将通过一次沉积单层或亚单层来构造界面，并且在界面形成时，将使用表面/界面分析工具来监测电子、化学和形态结构。该项目解决了材料科学领域的基础研究问题，具有高度的技术相关性。现在已有实验工具，可以在原子水平上观察基本表面过程，如果能更好地了解这些过程，就可以在基础科学和技术方面取得进展。从研究中获得的基本知识和理解，预计将有助于提高先进器件和电路的性能和稳定性，为设计和生产改进的材料和材料组合提供基本的理解和基础。 该计划的一个重要特点是通过在一个基本和技术上重要的领域对学生进行培训来整合研究和教育。

The goal of this proposal is achieve fundamental understanding though detailed interface analysis of existing and novel organic/inorganic and organic/organic structures relevant to the development of organic based thin film transistors(OTFT). The approach is to probe in detail the interface properties in model OTFT structures/devices. Attention will be focused on electronic structures, chemical reactions, interdiffusion, and charge transfer of the organic/metal, organic/organic and organic/dielectric interfaces from a microscopic or atomic viewpoint. The interface analysis will be coordinated with morphological and basic electrical characterization of the OTFTs. The objective is to provide a better understanding of the fundamental aspects of interface properties of organic semiconductors and to relate this interface knowledge to next generation OTFTs. Surface/interface analytical tools include x-ray photoemission spectroscopy (XPS), ultraviolet photoemission spectroscopy (UPS), inverse photoemission spectroscopy (IPES), near edge x-ray absorption fine structure (NEXAFS), and low energy electron diffraction (LEED). The interface/surface analysis will be supported by structural and electronic characterization, including atomic force microscopy (AFM), scanning capacitance-voltage (SCV), scanning tunneling microscopy (STM), and scanning tunneling spectroscopy (STS). The analysis will also be supplemented with device characterizations, including basic electrical characterization, internal photoemission, and electroabsorption. With controlled vapor deposition and in situ sputtering in an ultra-high vacuum (UHV) environment, the interface will be constructed by deposition of a monolayer or sub-monolayer at a time, and the electronic, chemical, and morphological structures will be monitored with surface/interface analytical tools as the interface is being formed. %%%The project addresses basic research issues in a topical area of materials science with high technological relevance. Experimental tools are now available to allow atomic level observation of elementary surface processes which when better understood allow advances in fundamental science and technology. The basic knowledge and understanding gained from the research is expected to contribute to improving the perform-ance and stability of advanced devices and circuits by providing a fundamental understanding and a basis for designing and producing improved materials, and materials combinations. An important feature of the program is the integration of research and education through the training of students in a fundamentally and technologically significant area.***