Porous-pyramids structured silicon surface with low reflectance over a broad band by electrochemical etching

Next-generation multi-crystalline silicon solar cells: Diamond-wire sawing, nano-texture and high efficiency

“…4(c), the nano-textured DWS mc-Si wafer had a double-scale surface texture, indicating a remarkable lighttrapping ability [24], which partly comes from the contribution of micron-sized oval pits ( $8% reduction in R from 36.73% to 28.5%) and is partly attributed to its nanostructure ( $ 13% reduction in R from 28.5% to 15.6%). The light-trapping mechanism of the nanostructure is usually attributed to the gradient-index, from n air ¼ 1 (refractivity of air) to n si ¼3.5 (refractivity of silicon) [25]. It should be noted that the pseudo pyramid nanostructure is formed after alkali etching.…”

Electrochemical etching of porous-pyramids structure with low reflectance

“…However, currently the reflectance of the pyramids structured silicon surface can only be reduced to above 10% in the visible range, which is still too high for high efficiency solar cells. Porous pyramids structured silicon is a promising antireflection coating to solve the problem of high surface reflectance in silicon solar cells [5]. During recent years, metal-assisted chemical etching (also called stain etching) has been developed to fabricate porous silicon and silicon nanowires.…”

Fabrication of black silicon via reactive ion etching through Cu micromask

“…To further reduce surface reflectance of silicon solar cells, 'black silicon' with a nanostructured surface has been created [1]. At present, the methods of fabricating black silicon include a femtosecond laser, metal-assisted wet etching, electrochemical etching and reactive ion etching (RIE) [2][3][4][5][6].…”