Known methods of producing large-surface integrated thin-film solar modules with an amorphous, poly- or microcrystalline absorber layer always comprise division and conversion structuring processes which can cause instabilities in the structuring and which are relatively expensive. A polymer material with a higher refractive index than that of the substrate is deposited within, and extends along, the channel, so as to define a waveguide. The obtained hash value is stored in association with the information included in the header field.