表面等离激元增强低功耗定点光控纳米焊接

The rapid development of information technology has been promoting the miniaturization, functionalization and integration of optical/mechanical/electronic devices. Nano-welding technology is essential in the fabrication of the micro/nano optical/mechanical/electronic devices. In particular, light-induced welding technology exhibits obvious advantages in operability, controllability and energy efficiency compared with other welding technologies. The light-induced nano-welding technology has only limited applications due to the shortcomings of high power-consumption and being difficult with targeted operation. To overcome these problems, we propose a novel low power consuming nano-welding technology based on the surface plasmon polariton (SPP)-induced field enhancement with continuum wave (CW) laser. The novelty of this technology lies in (1) utilizing SPP to localize and then enhance the electromagnetic fields, (2) coordinating the processes of light-heat conversion, heat transfer and localized melting, and (3) realizing low power-consumption, high-controllability and targeted nano-welding. In this proposal we focus our effects on solving three key scientific problems including achieving efficient light-heat conversion, regulating micro/nano temperature field and analyzing the dynamic processes of local melting and recrystallization. New light will be shed on the physical mechanisms of SPP-induced efficient light-heat conversion, heat transfer and localized melting. Further, a new CW controllable targeted nano-welding technology based on SPP-induced field enhancement will be developed. Finally, micro/nano functional devices will be fabricated with this new technology and this technology will also be expanded to practical applications (e.g. device repairing and wire bonding). The research results will be of great significance in developing novel micro/nano fabrication technology with proprietary intellectual property rights and promoting intercross of disciplines (e.g. micro/nano optics and electronics, advanced manufacturing and material sciences).

信息技术的高速发展推动光机电器件小型化、功能化和集成化。纳米焊接是微纳光机电器件加工的关键技术。光控焊接相比其他焊接，在操作性、可控性、能量利用效率等方面优势明显。针对目前光控无法实现定点低功耗纳米焊接现状，本项目提出表面等离激元增强低功耗定点光控(连续激光)纳米焊接。其技术创新在于：利用表面等离激元光场局域与增强，协同考虑光热转换、热输运和局部熔化三个过程，实现低功耗、高可控性定点纳米焊接。项目围绕定点低功耗纳米焊接这一科学目标，针对高效光热转换、微纳温度场调控、局部熔化及重结晶动态过程解析三个关键科学问题，研究表面等离激元增强光热转换、热输运和局部熔化的物理机理，开发表面等离激元增强低功耗定点光控纳米焊接技术并进行器件制备和应用拓展（如器件修复和引线键合）。研究成果对于发展具有自主知识产权的新型微纳加工技术和学科交叉性（微纳光学和电子学、先进制造、材料科学等）具有重要意义。

本项目围绕表面等离激元增强低功耗定点光控纳米焊接开展研究。项目在低功耗纳米焊接原理、技术、器件及应用方面取得进展，在Science Advance、 Laser and Photonics Review、Applied Physics Letters等国际知名期刊上共发表SCI论文10篇。项目培养博士生3人，硕士生3人。项目取得代表性研究成果包括：（1）理论方面：阐明了基于表面等离激元增强连续光控纳米焊接（包括光热转换、热输运和局部熔化三个过程）的物理机理和调控机制。（2）技术及器件方面：发展基于低功耗（亚毫瓦量级）定点光控（连续激光）纳米焊接技术；制备微纳光机电功能性结构和器件，如肖特基结等（基于Au80Sn20低熔点纳米光热钎焊技术和连续激光控制纳米焊接制备金属——半导体纳线异质结）。（3）应用拓展方面：基于低功耗定点光控（连续激光）纳米焊接技术，展示其在纳米修复和引线键合中的应用（连续激光控制纳米修复技术和连续激光控制三维纳米光热连接）。研究成果对于发展具有自主知识产权的新型微纳加工技术和学科交叉性（微纳光学和电子学、先进制造、材料科学等）具有重要意义。