Open AccessCurved periodic ripples fabricated by double time-delayed femtosecond laser beams on the silicon surface
Author(s) -
Chunhui Xiao,
Tingyuan Wang,
Xiaolei Wang,
Lin Liu,
Bing Gu,
Nan Zhang,
Weiwei Liu
Publication year - 2021
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.423709
Subject(s) - materials science , optics , femtosecond , laser , silicon , fluence , polarization (electrochemistry) , wavelength , laser scanning , beam (structure) , coaxial , optoelectronics , physics , chemistry , electrical engineering , engineering
Laser-induced periodic surface structure (LIPSS) is an important, high-throughput surface nano-structuring method, which has been used to fabricate various functional surfaces. In this paper, we fabricate double time-delayed orthogonally polarized femtosecond laser beams with a fixed beam power ratio of 1.5:1 that are employed to irradiate the silicon surface and curved periodic ripples with a sub-wavelength period. It is found that the local orientation of the ripples on the silicon surface can be modulated in a range of 0-80° by adjusting the fabrication parameters, such as the laser fluence, the target scanning speed, and the time delay between double laser beams. The transition from the curved ripples to the straight ripples can be achieved by increasing the target scanning speed. Different from previous studies that the curved periodic ripples are fabricated by modulating the laser polarization, the method demonstrated here utilizes the interaction between the linearly polarized subsequent laser beam and the preceding laser beam excited silicon to form curved ripples.