A method for densifying sol-gel films to form microlens structures includes preparing a sol-gel precursor, having at least one solvent therein. The sol-gel precursor is spin coated onto a wafer to form a sol-gel film thereon. The wafer and sol-gel film are hot plate baked at a temperature less than 200° C. to remove at least some of the solvent. The baked, wafer and spin-coated sol-gel film are treated with an oxygen plasma treatment to remove any remaining solvent and to densify the sol-gel film. The spin coating, hot plate baking and treating steps may be repeated as required. A microlens is formed from the densified sol-gel film.