Interfaces in Organic Thin Film Transistors

本提案的目标是通过对与有机基薄膜晶体管（OTFT）发展相关的现有和新型有机/无机和有机/有机结构的详细界面分析，获得基本的理解。该方法是详细探讨模型OTFT结构/器件的界面特性。将从微观或原子的角度关注电子结构、化学反应、相互扩散和有机/金属、有机/有机和有机/电介质界面的电荷转移。界面分析将与otft的形态和基本电特性相协调。目的是更好地理解有机半导体界面特性的基本方面，并将这种界面知识与下一代otft联系起来。表面/界面分析工具包括x射线光发射光谱（XPS）、紫外光发射光谱（UPS）、逆光发射光谱（IPES）、近边缘x射线吸收精细结构（NEXAFS）和低能电子衍射（LEED）。界面/表面分析将由结构和电子表征支持，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）。分析还将补充器件特性，包括基本的电学特性、内部光发射和电吸收。在超高真空（UHV）环境下，通过控制气相沉积和原位溅射，一次沉积单层或亚单层来构建界面，并在界面形成时使用表面/界面分析工具监测电子，化学和形态结构。该项目涉及材料科学中具有高技术相关性的主题领域的基础研究问题。现在有了实验工具，可以在原子水平上观察基本的表面过程，这些过程一旦得到更好的理解，就会促进基础科学和技术的进步。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基础和技术重要领域培养学生，将研究和教育相结合

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.***