Laser Application in Photovoltaics for Surface Texturization of Silicon and Front Electrode Deposition

Abstract The laser technology in the manufacturing of solar cells has become an indispensable element of modern photovoltaic technology. The main reason for taking up such research is because conventional methods used for monocrystalline silicon texturization are ineffective when applied to polycrystalline silicon texturing. This is related to random distribution of grains of different crystalographic orientations on the surface of polycrystalline silicon. Texturing a polycrystalline silicon surface using an Nd:YAG laser makes it possible to increase absorption of the incident solar radiation. The additional technological operation of etching in potassium hydroxide solution introduced into the technology of the photovoltaic cells manufactured from laser-textured wafers allows for improvement in electrical performance compared with cells produced from nontextured wafers. Moreover, this article presents the influence of selective laser sintering of front metallization that was manufactured using paste based on silver nanopowder on contact resistant. The electrodes were formed on monocrystalline silicon solar cells. The microstructures of laser-textured silicon and sintered front metallization were investigated by scanning electron microscope and confocal laser scanning microscope. The reflectance of produced textures was measured by spectrophotometer with an integrating sphere. Current-voltage characteristics of solar cells manufactured from laser-textured polycrystalline silicon wafer were measured under standard AM 1.5 radiation. The contact resistance between the metal and semiconductor was investigated using the transmission line model.