Laser Fluence Dependence of Nanodot Structures Formed on Silicon Solar Cell Surfaces

This study investigated the density and particle size distribution of nanodot structures formed on the surface of silicon solar cells by irradiation with a KrF excimer laser (248 nm). Silicon solar cell substrates were irradiated at the following laser fluences below or around the melting threshold of Fth_248 = 0.47 J/cm2. As laser fluence decreased, nanodot density initially increased, reaching a maximum value of 65 dots/µm2 at a laser fluence of 0.62 Fth_248. The average size of the nanodots showed a maximum value of 105.1 nm following irradiation at a laser fluence of 0.87 Fth_248 with the size decreasing at fluences lower than this value.