Ultrafast dynamics of femtosecond laser-induced high spatial frequency periodic structures on silicon surfaces  

作　　者：Ruozhong Han Yuchan Zhang Qilin Jiang Long Chen Kaiqiang Cao Shian Zhang Donghai Feng Zhenrong Sun Tianqing Jia 

机构地区：[1]State Key Laboratory of Precision Spectroscopy,School of Physics and Electronic Science,East China Normal University,Shanghai 200241,China [2]Institute of Laser Manufacturing,Henan Academy of Sciences,Zhengzhou 450046,China [3]Institute of Physics,Chinese Acadamy of Sciences,Beijing 100190,China [4]Collaborative Innovation Center of Extreme Optics,Shanxi University,Taiyuan 030006,China

出　　处：《Opto-Electronic Science》2024年第3期33-46,共14页光电科学（英文）

基　　金：supports from the National Natural Science Foundation of China(12074123,12174108);the Foundation of‘Manufacturing beyond limits’of Shanghai;‘Talent Program'of Henan Academy of Sciences.

摘　　要：Femtosecond laser-induced periodic surface structures(LIPSS)have been extensively studied over the past few decades.In particular,the period and groove width of high-spatial-frequency LIPSS(HSFL)is much smaller than the diffraction limit,making it a useful method for efficient nanomanufacturing.However,compared with the low-spatial-frequency LIPSS(LSFL),the structure size of the HSFL is smaller,and it is more easily submerged.Therefore,the formation mechanism of HSFL is complex and has always been a research hotspot in this field.In this study,regular LSFL with a period of 760 nm was fabricated in advance on a silicon surface with two-beam interference using an 800 nm,50 fs femtosecond laser.The ultrafast dynamics of HSFL formation on the silicon surface of prefabricated LSFL under single femtosecond laser pulse irradiation were observed and analyzed for the first time using collinear pump-probe imaging method.In general,the evolution of the surface structure undergoes five sequential stages:the LSFL begins to split,becomes uniform HSFL,degenerates into an irregular LSFL,undergoes secondary splitting into a weakly uniform HSFL,and evolves into an irregular LSFL or is submerged.The results indicate that the local enhancement of the submerged nanocavity,or the nanoplasma,in the prefabricated LSFL ridge led to the splitting of the LSFL,and the thermodynamic effect drove the homogenization of the splitting LSFL,which evolved into HSFL.

关 键 词：laser-induced periodic surface structures(LIPSS) local field enhancement collinear pump-probe imaging silicon high spatial frequency periodic structures 

分 类 号：TQ127.2[化学工程—无机化工] TN249[电子电信—物理电子学]