In a multilayer printed wiring board having a plurality of laminated resin
layers, a plurality of wiring patterns formed on the interfacial surface
of the resin layers, and a plurality of lands formed on the outermost
layer of the resin layers and on which the solder is provided, at least
one of the wiring patterns has a plurality of openings in the form of a
mesh, the size of openings of the wiring patterns in a region
corresponding to the position of solder in which a stress generated in
the solder provided on the lands becomes a value larger than a desired
value due to thermal deformation of the semiconductor device and the
multilayer printed wiring board is larger than that of openings in the
other regions.