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Metal‐assisted chemical etching (MAE) was used as an alternative route to texturise the front surface of multicrystalline Si solar cells. Ag nanoparticles deposited by an electroless method on the Si surface acted as catalysts for Si etching in a solution containing HF and H2O2, an oxidizing species. MAE formed a duplex structure at the surface of the Si wafer consisting in a mesoporous Si layer that after dissolution in NaOH revealed the second structure, which is a macrotexturised surface. After texturisation, the effective reflectivity (AM1.5G, 400‐1000 nm) ranged between 12% and 15% depending on the duration of the dissolution treatment of the mesoporous layer. MAE texturised solar cells were compared to NaOH texturised solar cells made with similar wafers (∼25% in effective reflectivity). MAE texturisation leads to a gain in fill factor (FF) but not in short‐circuit current (JSC) (from average values). The best MAE cell exhibited higher JSC (+2%) and efficiency (16.1%) compared to the best NaOH cell (15.7%). (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

The growth of epitaxial Si on (100)-oriented Si wafers in a horizontal rapid thermal chemical vapor deposition (RTCVD) reactor has been investigated. Trichlorosilane was employed as a precursor diluted in H 2 carrier gas at 1 atm reactor pressure. The growth rates in dependence of the deposition uniformity, the input partial pressure of the precursor, and the fluid dynamics were analyzed by a three-dimensional numerical simulation. Good agreement between predicted and measured growth rates were found. Moreover, the experimental growth rates under mass transport limitation were discussed in terms of gas-phase supersaturation and its impact on the surface morphology. Finally, it is demonstrated that hydrodynamic effects in the RTCVD reactor influence strongly the Si growth in the delivery rate limited regime.