碳铝硼三元化合物一维纳米结构及其光电特性

To be applied in future optoelectric device, there are mandatory features on the semiconductors, such as high thermal conductivity, high electron saturated mobility, high breakdown field and so on. As representative of the third generation semiconductors, although the research on diamond、SiC、ZnO and GaN has progress a lot in fundamental field, it is not enough to cover all of the required functionalities in future application. Based on the previous study of Al4C3, we find it is a good candidate as cold cathode emitter. Moreover, by introducing O element into Al-C, the strong ionic bond would be destroyed, which results in that Al4O4C exhibits the features of wide-band semiconductor with intense blue emission and optical waveguide behavior. This implies the possibility to seek for new type of the 3rd generation semiconductor in Al-C family. In this project, we would like to explore ternary C-Al-B compound systematically, which includes three aspects: (1) the design and fabrication of one dimensional C-Al-B nanostructure; (2) the investigation of the electric, optical and optoelectric properties; (3) the fabrication and performance test of optoelectric device. By doing these, we hope to extend the 3rd generation semiconductor family and realize more functionalities.

未来光电器件要求半导体材料具备高热导率, 高电子饱和速度，高击穿电场等属性，目前以金刚石, SiC, ZnO, GaN等宽禁带材料为代表的第三代半导体, 尽管在基础研究方面已取得了很大进展，然而有限的种类并不能满足所有器件需求。基于前期对Al4C3的系统研究，我们发现其具备较好的场电子发射能力; 通过引入氧元素打破Al-C间的强离子键，Al4O4C展现出宽带隙半导体的特征，具备极好的光子学行为，比如高强度蓝光发射和光波导，说明在Al-C体系中实现新型宽带隙半导体材料的可能性，本课题中, 我们拟将B元素引入到C-Al体系，系统地对C-Al-B三元化合物进行研究, 课题主要包含几个层面: (1)一维纳米结构设计与制备; (2)根据形貌与结构特点，从光学、电学以及光电特性等方面进行物性探索；(3)以所挖掘出的物性为依据，进行器件化研究。希望以此丰富第三代半导体家族，覆盖某些功能盲区。

无机材料的纳米线结构在诸多领域(光学，电学，光电子、力学等)具备应用前景。在实验室研究阶段，材料的制备以及基于单根线物性的研究为主要任务。在本项目当中，我们发展了合适工艺制备出Al3BC纳米线，WC纳米线，2H-SiC纳米线以及Al2O3纳米线，利用先进的微纳操纵与加工工艺，系统研究了其力学、光电特性。比如，初步确定Al3BC具有紫外光响应特性；首次发现WC纳米线具有~20%的临界弯曲应变以及表面非晶化行为，证明即使是硬质材料纳米线，同样可用于柔性器件当中；将高质量的2H-SiC纳米线纸制作成透明柔性、自支撑的紫外吸收与探测器，这是首次制备出高质量的SiC纳米线并发现光探测特性；基于Al2O3的色心动力学发展了一种纳米功能区编码与图案化的策略，并支持擦除与复写功能。这些成果极大的拓展了纳米线在各领域的应用前景。