硅烷寡聚物的合成及其导电性研究

【作者】 陈艳；

【导师】 肖胜雄；

【作者基本信息】 上海师范大学 ， 高分子化学与物理， 2017， 硕士

【摘要】 单分子电子学是纳米电子学的一个新兴子领域。最终目标是使用单分子作为电子电路中的活性组分。在过去的一个世纪,化学家已经对分子的结构是如何决定其电子性能的有了较为成熟的理解。将化学理论转化为设计和理解单分子电子器件,可推动此领域快速发展。本论文描述了我们通过有机硅的化学理论来控制单分子器件电荷传输和功能。单晶硅在半导体材料中占据着重要的地位,其化学结构是由Si-Siσ单键相互连接而形成的正八面体结构。金刚烷与单晶硅具有相同的空间结构,但两种材料的物理、化学、电学性能却有本质上的差异。分子形态是宏观单晶硅半导体材料的主要组成部分。由摩尔定律可知,半导体器件尺寸会越来越小,硅电子器件也有同样的趋势。当硅电子器件尺寸从宏观状态变成小分子尺度——单个有机硅分子,宏观下的电学规律将不再适用。因此研究纳米尺度下有机硅分子的电子行为具有非常重要的科学意义。目前已知,导电通路和分子张力是影响单分子电导的重要因素,我们期望通过对这两个因素的可控调节,来研究它们对有机硅分子电导性能的影响。我们使用扫描隧道显微镜断裂(STM-BJ)技术来探测有机硅分子导线的结构-电导率关系。我们的研究最终证明在这些系统中的电荷传输是由单分子的构象、共轭和σ-骨架的键极性决定。第1章介绍了单分子电子学、硅微电子学和有机硅烷化学,以及我们将这三个方面连接起来的原因。第2、3章详细阐述了本论文合成有机硅分子的详细过程。第4章则对合成物质的导电性测试结果进行分析。更多还原

【Abstract】 Single-molecule electronics is an emerging subfield of nanoelectronics where the ultimate goal is to use individual molecules as the active components in electronic circuitry.Over the past century,chemists have developed a rich understanding of how a molecule’s structure determines its electronic properties;transposing the paradigms of chemistry into the design and understanding of single-molecule electronic devices can thus provide a tremendous impetus for growth in the field.This dissertation describes how we can harness the principles of organosilicon chemistry to control charge transport and function in single-molecule devices.Bulk silicon,the bedrock of information technology,consists of the deceptively simple electronic structure of just Si-Si σ bonds.Diamond has the same lattice structure as silicon,yet the two materials have dramatically different electronic properties.Molecular forms are the essential components of the bulk semiconductor.Moreover,as silicon electronics continues to scale to smaller length scales the connection between molecular silicon and silicon from bulk single crystals will become more explicit.In silicon electronics,conductive path and strain of the molecular has been found to an important parameter to insert and control to maximize performance.We use a scanning tunneling microscope-based break-junction(STM-BJ)technique to probe structure-conductivity relationships in silicon-based wires.Our studies ultimately demonstrate that charge transport in these systems is dictated by the conformation,conjugation,and bond polarity of the σ-backbone.Chapter 1 introduces the fields of single-molecule electronics,silicon microelectronics and our motivation for bridging these three worlds.The detailed processes of synthesizing organosilicon molecules are described in detail in Chapter 2and 3.Chapter 4 analyzes the conductivity test results of synthetic materials.更多还原