脉冲激光沉积法层状IGZO薄膜的外延有序排列和载流子传输调控

Crystalline (0001) oriented IGZO (In-Ga-Zn-O) based thin film transistors (TFTs), representative of metal oxide TFTs, have attracted great attention worldwide due to their potentials in commercialization of relevant novel displays. The epitaxial orderly arrangement of layer-by-layer IGZO thin film refers to not only the c-axis (0001) alignment like a crystal, but also regular hexagonal arrangement in ab plane. In order to achieve almost perfect crystal in layered structure epitaxial IGZO film for the pursuit of high carrier mobility and high reliability of TFT, pulsed laser deposition is implemented in this project to induce sufficiently and in situ monitor the crystallization process of IGZO films. Critical control mechanism of the dependence of layer-by-layer epitaxial growth as well as quantification of IGZO crystallization, on spectroscopic characteristics and carrier transport properties will be revealed. The correlation between epitaxial growth of IGZO and mobility, threshold voltage, on/off ratio, together with reliability of TFT will be established. These explorations including the epitaxial orderly growth, carrier transport control, and improvement of.TFT reliability in layered structure IGZO will provide significance in basic research and original value to advanced applications of IGZO ranging from high resolution smart phone, large size and 3D TV, to flexible or transparent displays.

以结晶取向(0001)IGZO(In-Ga-Zn-O)为代表的金属氧化物薄膜晶体管 (TFT)正受到全世界学者的高度关注。层状IGZO薄膜的外延有序排列，指IGZO薄膜不仅在c轴(0001)方向结晶，而且在 ab面内遵循规则的正六边形排列。为实现几近完美晶体结构的层状外延IGZO薄膜，获得高载流子迁移率、大幅度提升TFT稳定性，采用脉冲激光沉积法对IGZO薄膜结晶过程充分诱导和原位监测，揭示IGZO薄膜c轴层状生长和ab面内有序的关键性调控机制、并对IGZO薄膜结晶程度定量化，实现对IGZO薄膜光谱性能、载流子输运性能的控制，建立IGZO薄膜的外延生长和TFT器件阈值电压、开关比以及稳定性的优选关系。通过层状IGZO薄膜的外延有序生长、载流子传输控制、TFT器件稳定性提升等方面探索，将会对高分辨率智能手机、大尺寸三维显示、柔性显示、透明显示等高端应用具有重要的基础研究价值和开创性启发意义。

本项目系统研究了两种系列的IGZO薄膜，In元素系统变化的一系列IGZO薄膜，Ga元素系统变化的一系列IGZO薄膜，并针对薄膜性能进行详细讨论。采用溶胶凝胶法生长IGZO 薄膜，考察溶液配比、沉积温度、衬底类型等参数对IGZO薄膜微观结构和结晶特性的影响规律，探索IGZO薄膜的最佳生长工艺条件，得到膜厚、结晶程度和表面形貌可控的一系列IGZO薄膜。采用磁控溅射方法生长GZO 薄膜。通过X射线衍射（XRD）、扫描电子显微镜（SEM）及能谱（EDS）、辉光放电质谱（GD-ES）、紫外可见分光光度计、光致发光谱等方法分析薄膜的结晶结构及成分组成；综合评估IGZO薄膜的生长工艺条件和结晶性能，为器件制作提供基础数据和科学指导。.此外，本项目研究了器件制作时掩膜板的设计（见附件5），IZGO薄膜作为有机发光二极管有源层时的总体设计思路（见附件6）。本项目研究了硅薄膜的两种结晶化方式（见附件3）。本项目研究ZnO外延薄膜的低温发光光谱（见附件1），研究其在低温状态下的物理属性。研究ZnO的重要用途之一电能无线传输LED发光二极管（见附件7），研究ZnO与石墨烯复合材料的光催化性能（见附件4）。研究F16CuPc/CuPc 有机异质结作为生物DNA检测的应用（见附件2）。