Defect Free and Robust Microstructuring Using Femtosecond Axicon-lens-focused Beam (FAB) with Application Focus in Thin Film Solar Cell Manufacturing

本研究项目的目的是研究飞秒近无衍射激光与太阳能薄膜等先进材料之间的物理相互作用，并揭示此类材料微结构中的烧蚀机理。研究方法将包括实验研究和数值模拟。将进行一项全面的实验研究，以评估激光整形和操作参数对工艺稳健性、效率和切割质量的影响。为了阐明激光烧蚀的基本机理和优化工艺条件，将建立一个激光烧蚀模型。这项工作的成功完成将产生飞秒激光与先进材料相互作用领域的新的基础知识。这一新知识将为发展新的飞秒激光微加工工艺奠定科学基础。拟议的微结构工艺在许多领域都有应用，包括太阳能电池的划片、微型机电系统和发光二极管的微加工、汽车和航空航天工业中的微钻孔、摩擦学部件的表面纹理等。例如，在太阳能行业，使用拟议的划片工艺将显著提高薄膜太阳能电池板的转换效率。再加上通过卷筒式批量生产大幅降低成本的潜力，该项目将为国家-S清洁能源未来无空气污染、危险废物和全球变暖做出贡献。除了对制造业的影响外，还将开发引人入胜的教材和活动，以培养不同的本科生和研究生群体，并教育K-12学生和普通公众。

The objective of this research project is to study the physical interactions between a femtosecond near-nondiffracting laser beam and advanced materials such as solar thin films and reveal the ablation mechanisms in microstructuring of such materials. Research approaches will include both experimental investigation and numerical modeling. A comprehensive experimental study will be conducted to assess the effects of laser beam shaping and operating parameters on process robustness, efficiency and cut quality. A laser ablation model will be developed to elucidate the basic ablation mechanisms and to optimize process conditions. The successful completion of this work will generate new fundamental knowledge in the area of femtosecond laser interaction with advanced materials. The new knowledge will serve as the scientific foundation based on which new femtosecond laser micromachining processes can be developed. The proposed microstructuring process has applications in numerous areas including scribing of solar cells, micromachining of microelectromechanical systems and light-emitting diodes, microdrilling in automotive and aerospace industry, surface texturing for tribological components, etc. In the solar industry, for example, a significant increase in conversion efficiency for thin film solar panels will be achieved using the proposed scribing process. Together with the potential of significantly reducing cost through roll-to-roll mass production this project will contribute to the nation?s clean energy future free of air pollution, hazardous waste, and global warming. Besides impacts on manufacturing industry, fascinating education materials and activities will be developed to train a diverse group of undergraduate and graduate students and to educate K-12 students and the general public.