Efficient Broadband Light-Trapping Structures on Thin-Film Silicon Fabricated by Laser, Chemical and Hybrid Chemical/Laser Treatments

Light-trapping structures formed on surfaces of various materials have attracted much attention in recent years due to their important role in many applications of science and technology. This article discusses various methods for manufacturing light-trapping black silicon, namely laser, chemical and hybrid chemical/laser ones. In addition to the widely explored laser texturing and chemical etching methods, we develop a hybrid chemical/laser texturing method, consisting in laser post-texturing of pyramidal structures obtained after chemical etching. After laser treatments the surface morphology was represented by a chaotic relief of microcones, while after chemical treatment it acquired a chaotic pyramidal relief. Moreover, laser texturing of preliminarily chemically microtextured silicon wafers is shown to take five-fold less time compared to bare flat silicon. In this case, the chemically/laser-treated samples exhibit average total reflectance in the spectral range of 250-1100 nm lower by 7-10% than after the purely chemical treatment.

Automated summary

Light-trapping structures on various material surfaces have gained significant attention for their role in science and technology. This article explores different methods for manufacturing light-trapping black silicon, including laser, chemical, and hybrid methods. The authors introduce a hybrid chemical/laser texturing method, combining laser post-texturing with pyramidal structures obtained from chemical etching. The results show that laser texturing of chemically microtextured silicon wafers takes significantly less time and results in lower reflectance compared to purely chemical treatment.