A method for soldering an insulating substrate onto a substrate mounting portion of a carrier by a predefined solder is provided. The insulating substrate includes a dielectric insulation carrier, a top side, and a bottom side opposite to the top side. The method includes selecting the insulating substrate based on a criterion which indicates that the insulating substrate, if it has the solidus temperature of the solder, has a positive unevenness. The insulating substrate is soldered on the bottom side to the substrate mounting portion, such that, after the soldering, the solidified solder extends continuously from the bottom side of the insulating substrate as far as the substrate mounting portion. The top side of the insulating substrate is populated with at least one semiconductor chip.