Semiconductor device having a first substrate containing circuit element connected to radiation plate on a cover plate with metal vias

A semiconductor device comprising:

• a first substrate;
• a circuit element formed on a front surface of the first substrate and having a plurality of electrodes;
• a second substrate having a first face and laminated on the first substrate so that the first face of the second substrate faces the front surface of the first substrate, the second substrate having a plurality of via holes respectively arranged on the plurality of electrodes;
• and
• a plurality of metal layers respectively formed inside of the plurality of via holes the plurality of metal layers connecting with the plurality of electrodes;
• and
• a plurality of radiation plates formed on a second face of the second substrate and respectively connected to the plurality of metal layers,
• wherein the second substrate has a plurality of protruding portions which are formed so as to protrude from the first face and to connect with the plurality of electrodes, the plurality of protruding portions being made of the same material as that of the second substrate and being formed on the first face so as to be spaced apart from each other,
• the plurality of via holes penetrate through the second substrate and the plurality of protruding portions, and
• there are spaces between the plurality of protruding portions of the second substrate.