A package structure for a semiconductor device comprises a substrate
having a main surface and a back surface, a semiconductor chip formed on
the main surface of the substrate, a package covering the semiconductor
chip, radiation protrude electrodes and connection protrude electrodes.
The radiation protrude electrodes are formed on the back surface of the
substrate in a chip area where said semiconductor chip is located. Each
of the radiation protrude electrodes are formed with a first pitch so
that the radiation protrude electrodes make one body joining layer when
the package structure is subjected to a heat treatment. The connection
protrude electrodes are formed on the back surface of the substrate in a
peripheral area of the chip area. Each of the connection protrude
electrodes formed with a second pitch which is larger than the first
pitch so that the connection protrude electrodes stay individual when the
package structure is subjected to a heat treatment.