近日，吉林大学的孙洪波&陈岐岱及其研究小组与澳大利亚斯威本科技大学的Saulius Juodkazis等人合作并取得一项新进展。经过不懈努力，他们实现具有纳米精度的透明固体超隐身切割。相关研究成果已于2024年5月8日在国际知名学术期刊《自然—光子学》上发表。
据悉，半导体晶圆和透明介质的激光切割技术已成为制造业的主流工艺，广泛应用于从显示面板到微电子芯片等多个领域。然而，由于光束宽度的衍射极限和激光聚焦的纵向范围限制，传统激光加工在切割精度和宽深比之间需要做出权衡。通常，其精度接近1微米，而宽深比则达到100数量级。
该研究团队提出了一种突破这一限制的创新方法。该方法基于反向散射干涉爬行机制，通过入射光束与激光诱导的纳米种子反向散射光的干涉，形成了一个正反馈回路。这种机制有效地实现了激光与物质相互作用时纵向能量沉积的均匀化，并限制了侧向亚波长光的传播。研究人员成功实现了在几十纳米范围内的切割宽度，且宽深比高达1000到10000。研究人员将这一技术命名为“超级隐形切割”，并通过数值模拟对其进行了验证。
这项技术可应用于各种透明功能固体，如玻璃、激光晶体、铁电和半导体材料，从而有望提高未来先进的激光切割、图案和钻孔的精度。
附：英文原文
Title: Super-stealth dicing of transparent solids with nanometric precision
Author: Li, Zhen-Ze, Fan, Hua, Wang, Lei, Zhang, Xu, Zhao, Xin-Jing, Yu, Yan-Hao, Xu, Yi-Shi, Wang, Yi, Wang, Xiao-Jie, Juodkazis, Saulius, Chen, Qi-Dai, Sun, Hong-Bo
Issue&Volume: 2024-05-08
Abstract: Laser cutting of semiconductor wafers and transparent dielectrics has become a dominant process in manufacturing industries, encompassing a wide range of applications from display panels to microelectronic chips. Constrained by the diffraction limit of the beam width and the longitudinal extent of the laser focus, a trade-off between the cutting accuracy and the aspect ratio is inherent to conventional laser processing, with the accuracy typically approaching one micrometre and the aspect ratio of the order of 100. Here we propose a method to circumvent this limitation. Our method exploits a mechanism of back-scattering interference crawling in which the incident beam interferes with light that is back-scattered by laser-induced nanoseeds, creating a positive feedback loop. This mechanism ensures both homogenization of longitudinal energy deposition and confinement of lateral subwavelength light during laser–matter interactions. We achieve cutting widths in the range of tens of nanometres with aspect ratios ranging from 1,000 to 10,000. We refer to this technique as ‘super-stealth dicing’ and we validate it through numerical simulations. The technique can be applied to various transparent functional solids, such as glass, laser crystals and ferroelectric and semiconductor materials, thus promising enhanced precision for future advanced laser dicing, patterning and drilling.
DOI: 10.1038/s41566-024-01437-8
Source: https://www.nature.com/articles/s41566-024-01437-8