Rough black silicon optimal for solar cells

‘Black silicon is made when the surface of regular silicon is etched to produce tiny nanoscale pits on the surface. These pits change the color of the silicon from gray to black and, critically, trap more light, an essential feature of efficient solar cells…As flourine gas etches away at the silicon unevenly, pits are created on the surface of the silicon. The rougher the surface, the more light it can absorb, making rough black silicon ideal for solar cells’

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