Textured monocrystalline thin‐film Si cells from the porous silicon (PSI) process

Abstract

We have fabricated a textured monocrystalline Si solar cell with a thickness of 15Á5 lm and a con®rmed ef®ciency of 12Á2% using porous silicon (PSI) for layer transfer. The PSI process avoids photolithography and high-temperature oxidation. The cell has a surface that is textured with randomly positioned inverted pyramids for light trapping. The device does not yet fully exploit the light-trapping capability of this ®lm shape, owing to a small back-surface re¯ectance.

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