A method for soldering a first soldering partner (2) onto a mounting surface (3t) of a second soldering partner (3), wherein the first soldering partner (2) has an upper side (2t) and a lower side (2b) opposite the upper side (2t), and wherein the method comprises: arranging a solder (5) between the mounting surface (3t) and the bottom (2b) and melting the solder (5) such that at a first time - the first solder partner (2) at a first location (S1) the underside (2b) bears against a spacer (41); - The first solder partner (2) at a second location (S2) of the bottom (2b) bears against a spacer (42); - A third point (S3) of the bottom (2b) of the first soldering partner (2) from the mounting surface (3t) has a first distance (d1); Pressing together of the first soldering partner (2) and the second soldering partner (3) such that from a second time following the first time the third point (S3) of the bottom (2b) of the first soldering partner (2) from the mounting surface (3t) a second Distance (d2) which is smaller than the first distance (d1) and, during the pressing together, cooling the solder (5) to below its solidus temperature, so that it forms a solid bonding layer extending continuously from the mounting surface (3t ) extends to the lower side (2b) of the first soldering partner (2), one of the first soldering partner (2) and the second soldering partner (3) being designed as a base plate for a power semiconductor module and the other as a circuit carrier; wherein the first distance (d1) is greater than the second distance (d2) by at least 25 μm; and wherein the circuit carrier (2) is equipped with a semiconductor chip (1) before arranging the solder (5) between the mounting surface (3t) and the bottom (2b) or after the solder (5) has cooled below its solidus temperature.
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