Time-resolved microscopy and model-based analysis of Transparent Conductive Oxides thin-film ablation by spatial and temporal shaped ultrashort pulsed laser radiation

在这个项目中，对所谓的局部和间接诱导激光烧蚀透明导电层的基本理解是利用超短脉冲激光辐射应用于ITO（氧化铟锡）。结果是通过仿真和实验数据得到的元模型形式的描述。通过选择性地使用这种激光诱导烧蚀，导电结构被分离或构造，为组件产生功能表面，例如发光二极管的前电极。由于终端组件通常由几层厚度在几十到100纳米之间的薄膜组成，因此去除ITO层边缘区域的跳变等缺陷可能导致短路，从而导致组件失效。为了控制甚至防止这种缺陷，彻底了解烧蚀过程和所涉及的物理相互作用是必要的。为了确定这些机制，烧蚀过程的驱动力，并指导数学物理模型的发展，研究了实验过程的观测值，它描述了该过程的动力学和能量学。仿真和实验结果用于元模型的迭代开发。元模型是一个计算查找表，用于连续逼近参数和标准（流程图）之间的关系。与单次模拟运行或实验的数据分析相比，元模型允许使用严格的数学方法对插值的任意密集数据进行全局分析。在项目结束时，开发的元模型有望预测可测量和可验证的目标变量，如光栅高度、基板损坏、绝缘电阻和裂纹长度作为工艺参数的函数。

In this project, a basic understanding of the so-called partial and indirectly induced laser ablation of transparent, conductive layers using ultra-short pulsed laser radiation applied to ITO (Indium Tin Oxide) is to be developed. The result is a description in the form of a Metamodel, which is obtained from simulations and experimental data. By selective use of this laser-induced ablation, electrically conductive structures are separated or structured producing functional surfaces for components, such as front electrodes of a light-emitting diode. Since the end components often consist of several thin films with layer thicknesses in the range of a few tens to 100 nanometers, defects such as jumps in the edge area of the ITO layer removed can lead to short circuits and consequently to failure of the component. To manipulate or even prevent such defects, a thorough understanding of the ablation process and the physical interactions involved is necessary.In order to identify these mechanisms, the driving forces of the ablation process and to guide the development of a mathematical-physical model, experimental process observables are investigated, which describes both the dynamics and the energetics of the process. The simulative and experimental results are used for the iterative development of a Metamodel. A Metamodel is a computational look-up table for the continuous approximation of the relation between parameters and criteria (process map). Compared with the analysis of data from single simulation runs or experiments, the Metamodel allows a global analysis using rigorous, mathematical methods on interpolated, arbitrarily dense data. At the end of the project, the developed Metamodel is expected to predict measurable and verifiable target variables such as grating heights, substrate damage, insulation resistances and crack lengths as a function of the process parameters.