超光电子铜箔的微尺度激光冲击平坦化  

Microscale Laser Shock Flattening of Ultrasmooth Electronic Copper Foil

作　　者：赵恩兰[1,2] 王情情 杨海峰 彭玉兴[1,2] Zhao Enlan;Wang Qingqing;Yang Haifeng;Peng Yuxing(School of Mechatronic Engineering,China University of Mining and Technology,Xuzhou 221116,Jiangsu,China;Jiangsu Collaborative Innovation Center of Intelligent Mining Equipment,Xuzhou 221116,Jiangsu,China)

机构地区：[1]中国矿业大学机电工程学院,江苏徐州221116 [2]江苏省矿山智能采掘装备协同创新中心,江苏徐州221116

出　　处：《中国激光》2022年第16期10-19,共10页Chinese Journal of Lasers

基　　金：国家自然科学基金(52105494);中央高校基本科研业务费专项资金(2020QN58)。

摘　　要：根据激光冲击的原理对超光电子铜箔进行了微尺度激光冲击平坦化(MLSF)处理。首先,通过MLSF实验研究脉冲能量和冲击次数等工艺参数对电子铜箔平坦化效果(表面粗糙度S_(a))的影响规律;然后,根据电子铜箔平坦化效果与工艺参数的对应规律,阐明电子铜箔的MLSF原理;最后,采用透射电子显微镜对MLSF处理前后的电子铜箔进行显微表征,揭示电子铜箔MLSF的表面变形机理。研究结果表明:当激光脉冲能量为100μJ、冲击次数为3次时,电子铜箔的表面粗糙度(S_(a))从22.7 nm降低到5.0 nm,降低了78%;冲击波经吸收层和样品层后被放大,使得样品层(铜箔)与底板(玻璃)的表面形貌接近;金属箔内部的小塑性变形和下表面附近的大塑性变形是MLSF的表面变形机制。Objective Electronic copper foil is an important material for circuit boards and plays an essential role in interconnecting circuits and electronic components.Ultrasmooth electronic copper foils are a crucial for manufacturing high-end circuit boards.However,traditional polishing methods have some limitations in the high-efficiency polishing of large-area ultrathin metal foils.Laser shock peening and forming is a manufacturing technology that uses ultrahigh pressure and higlrspeed shock force generated by a short-pulse laser to achieve a high strain rate plastic deformation of materials.The laser shock peening can improve the material’s comprehensive mechanical properties by inducing grain refinement and residual compressive stress on its surface.Through shock wave pressure,the laser shock imprinting causes plastic deformation to form a metal foil,allowing for fabricating micro and nanostructures on the metal foil surface,which can be used in electronic and plasma sensing.Because the laser shock technology can cause plastic deformation on the metal foil surface,it can enable the surface polishing of electronic copper foils.It has been reported that a shock wave generated by a high-energy pulsed laser strikes the metal foil with the bottom plate to duplicate the smooth surface of the bottom plate and obtain less surface roughness of the metal foil.However,because of the large pulse energy and spot size,large plastic deformation occurs,causing profile fluctuation of the spot transition zone.Therefore,studying the microscale laser shock flattening(MLSF)of electronic copper foils using a low-energy pulsed laser is important.Methods The MLSF experimental device comprised a pulsed laser,beam expander and collimator,galvanometer system,and target.The pulse width,wavelength,and repetition frequency of the laser were 10 ns,355 nm,and 1 kHz,respectively.The collimated laser beam was scanned using a galvanometer and was focused on the surface of an electronic copper foil,with a focusing diameter of 20μm.The morphology an

关 键 词：激光技术 激光冲击 微尺度 电子铜箔 表面粗糙度 表面变形机理 

分 类 号：TN249[电子电信—物理电子学]