Fabrication of multi-crystalline silicon pyramid structure and improvement in its photovoltaic performance

The texture structure of the multi-crystalline silicon (mc-Si) pyramid was realized by a combination of acidic and alkaline etching. The results showed that the structure of the corrosion pits could be first obtained on the mc-Si surface by acid etching, and the subsequent alkaline etching could further transform the pits into a pyramid structure. The best solar cell obtained based on the textured structure showed superior photovoltaic property, and its photovoltaic conversion efficiency reached 18.17%, which was significantly higher than that of solar cell without texture structure. The improvement in efficiency was mainly owing to the light-trapping effect of texture structure, which was confirmed by the external quantum efficiency measurement. This work offers a simple way to prepare low-cost mc-Si solar cells with high performance.