Effectiveness of anisotropic etching of silicon in aqueous alkaline solutions

Correlation between reflectivity and photoluminescent properties of porous silicon films

“…As shown by Singh et al [10], the reflectivity of a (100) oriented Si wafer textured in a NaOH solution at~80°C for etching durations of 10-35 min is nearly constant in 500-1000 nm wavelength range and has a value 15-25%. The reflectivity values are higher than the above values for A< 500 and }, > 1000 nm.…”

“…The reflectivity values are higher than the above values for A< 500 and }, > 1000 nm. Application of an ARC on the textured Si wafer reduces the reflectivity for all wavelengths below 1000 nm [10]. PS layers of suitable thicknesses have also been used as single layer ARC on Si solar cells having textured or polished front surface [11,12].…”

Effect of low thermal budget annealing on surface passivation of silicon by ALD based aluminum oxide films

“…The reflectivity of the films is measured using a spectrophotometer fixed with an integrating sphere (Model: PVE 300, M/s Benthem, UK with an integrating sphere DTR6). To ensure the correctness of the measured reflectivity values, the measurements are done after baseline (i.e., back ground) correction using standard high purity BaSO 4 powder pressed in the form of a pallet. Fourier transform infrared spectroscopy (Model 2000, M/s Perkin Elmer spectrometer, USA) is used to get information about the surface bonding.…”

“…It is reported that a band at 564 cm À1 results from two unresolved structures at 562 and 565 cm À1 . The first one is assigned to Al-O bending for AlO 6 (5 + 1), while the second to a pure Al-O stretching mode for AlO 4 . 36 The peak observed in the 560-570 cm À1 region (a minor shift with d Al 2 O 3 ) represents Al-O modes.…”

“…In order to reduce the cost of silicon solar cells made on expensive wafers (high quality silicon), thinner substrates (to reduce the usage in terms of watt g À1 ) are required. 2,3 A reduction in thickness and surface modification (either by anisotropic 4 or nano-texturisation 5 ) to reduce reflection losses leads to the increase of the surface to volume ratio and, consequently, the surface recombination becomes a dominant loss factor. 6 This affects the solar cell performance parameters adversely.…”