The subject of the invention is a transparent substrate, especially a glass substrate, provided with a thin-film multilayer acting on solar radiation, the multilayer being deposited by magnetron sputtering, characterized in that it includes at least a lubricating film of high optical index n, this lubricating film being associated with at least one sublayer, which is based on silicon nitride or oxynitride or carbonitride, or based on aluminum and/or zirconium nitride or oxynitride or carbonitride, or a mixture of at least two of these compounds (mixed Si—Al or Si—Zr nitrides or oxynitrides or carbonitrides).