自支撑硅氧碳纳米镶嵌复合薄膜的氧空位调控与发光机制研究

项目名称： 自支撑硅氧碳纳米镶嵌复合薄膜的氧空位调控与发光机制研究

项目编号： No.51302237

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 一般工业技术

项目作者： 姚荣迁

作者单位： 厦门大学

项目金额： 25万元

中文摘要： 降低晶格错配和提高发光效率是当前SiC薄膜广泛应用于微机电系统（MEMS）及高温短波光电子器件等领域的研究重点，项目针对SiC薄膜/基材界面缺陷多及发光效率低的难题，以聚碳硅烷（PCS）和改性PCS为原料，基于先驱体熔融纺膜技术制备出新型硅氧碳纳米镶嵌复合薄膜，具有禁带宽度及氧空位发光中心密度大、致密度高、自支撑及化学稳定性好等结构功能一体化特性，以及纳米β-SiC镶嵌SiOxCy/Cfree复合结构模型。采用不同分子结构PCS来调控薄膜氧空位的形成和发光性能，获得多空位硅氧碳纳米镶嵌复合薄膜先驱体分子结构的设计准则。着重研究薄膜氧空位浓度对其发光特性的影响机制，并获得薄膜发光宽带隙模型与双空位缺陷中心发光机理，阐明其关键控制因素，探讨提高光电性能的有效措施，研究结果可指导复合薄膜的质量控制和组分、微结构的创新设计，实现其发光稳定与效率增大以及在高温蓝紫光学器件、MEMS等领域的成功应用。

中文关键词： 结构功能一体化；先驱体熔融纺膜；硅氧碳纳米镶嵌复合结构；氧空位；发光模型

英文摘要： Silicon carbide (SiC) films with a combination of unique physicochemical and mechanical properties are well known as an important ceramic coatings for applications in the next generation of high-power, advanced optoelectronic devices and power microelectromechanical systems (MEMS). Considerable current attention has been focused on reducing the mismatches of thermal expansion coefficient and lattice constant resulted from heteroepitaxial techniques and improving the luminescent efficiency of SiC films. In the present study, a novel technique based on melt spinning of precursor was introduced to produce freestanding β-SiC/SiOxCy/Cfree nanocomposite films which could avoid the significant difference of thermal expansion coefficient between SiC and substrate. The as-received films exhibit several advantages such as wide band gap, high density of the oxygen mono- and di-vacancy defect centers, good radiation resistance, high hardness and chemical inertness. The structural-functional freestanding nanocomposite films are also explored as one of the most outstanding luminescent materials to improve the blue luminescent efficiency and stability. The radiative recombination of carriers can be ascribed to the oxygen mono- and di-vacancy from SiOxCy at the surfaces of β-SiC nano-crystals, whereas the photogeneration of car

英文关键词： Structure-function；Melt spinning；β-SiC /SiOxCy/C nanocomposite structure；Oxygen vacancies；Photoluminescence model