Authors:
Z. Zhang
CNM and JR3CN, Changchun University of Science and Technology, Changchun 130022, China and CHO, Changchun Observatory, National Astronomical Observatory, CAS, Changchun 130117, China

Z. Wang
D. Wang
CNM and JR3CN, Changchun University of Science and Technology, Changchun 130022, China and JR3CN, University of Bedfordshire, Luton LU1 3JU, United Kingdom

Y. Ding
CNM and JR3CN, Changchun University of Science and Technology, Changchun 130022, China

Silicon surface structures with excellent antireflection property arouse wide interest. Chemical and physical methods such as femtosecond, nanosecond, and picosecond laser processing, wet-chemical etching, electrochemical etching, and reactive ion etching have been developed to fabricate them. However, the methods can only produce a quasi-ordered array of sharp conical microspikes on silicon surface. In this paper, we present a method to fabricate periodic silicon antireflection surface structures using direct four-beam laser interference lithography (LIL). With 1 atm ambient atmosphere of SF₆ and the laser fluence of the four beams irradiated on the silicon surface at 0.64 J cm⁻², the periodical conical spikes were generated. Changing the polarization directions of the opposite incident beam pairs in a four-beam LIL system could convert conical spikes structure into an array of holes. Antireflection in a wide spectral range was measured by a spectrophotometer from ultraviolet to near-infrared. The average reflectance of this periodic black silicon surface is less than 3.5%.