the plan view of the front side 2 a in this case the vertex of the minimum angle u03c6 0 is given by the center m of curvature assigned to the smallest radius of curvature that occurs in the edge portion in the case where an edge portion includes the smallest radius of curvature at a plurality of locations a minimum angle u03c6 over which the recess 9 at least extends may be assigned to each of the centers m of curvature assigned to said locations the criteria described in fig2 using the example of an outer corner 2 c of the connecting area 2 b may be applied in the same way to any desired edge location or to any desired edge portion of the connecting area 2 b to the region of inner corners 2 d as illustrated by way of example in fig1 to 15 17 18 and 20 fig2 illustrates a plan view of a portion of a baseplate 2 of a power semiconductor module according to an embodiment which includes a connecting area 2 b a fixing location 3 spaced distant from the latter and also a recess 9 arranged between the connecting area 2 b and the fixing location 3 a radius r of curvature and a center m of curvature may be assigned to each edge point of the connecting area 2 b proceeding from said.