We investigate the effect of surface texturing on the light trapping properties of Silicon wafers as a
function of reflection reduction and surface morphology. This was achieved by structuring a
random square-based pyramids pattern on the surface of Silicon substrate using anisotropy etching.
The light trapping effect was optimized for silicon solar cells by investigating the dependence of the
silicon surface texturing on the process parameters such as etchant concentration, etching time and
temperature. We study the surface morphology by analyzing the surface behaviour of the textured
substrate using the atomic force microscope and scanning electron microscope. The results of
roughness and optical reflection were obtained using the surface profiler and the UV/VIS the
spectrometer respectively. In addition, an analytical modelling method was developed to determine
the angles of incidence of light rays with each of the facets of the pyramids and the coordinate of
the reflected light rays. The method used here is based on 3-D vector geometry of the pyramidal
facets. The optimum parameters are found to be 40min, a temperature of 80oC and with
KOH/IPA/DI in the ratio [2:4:46] by volume, yielding a surface roughness over 600 nm and a
relative optical reflectance in the visible spectrum less than 10%, using polished Si as reference.
The results and analysis of both the modelled and measured reflectance, suggest that the
performance of the light trapping technique has a big potential in silicon solar cells application.