Semiconductor device with stack of semiconductor chips

Claim 1

A semiconductor device comprising: a substrate having a first plurality of pads and a second plurality of pads; a first semiconductor chip mounted on said substrate and having a third plurality of pads; a plate member arranged on said first semiconductor chip and having an end at an inward position of said first semiconductor chip adjacent to the third plurality of pads; a second semiconductor chip arranged on said plate member and having a fourth plurality of pads; a first structure and a second structure respectively and electrically interconnecting said third plurality of pads with said first plurality of pads and said fourth plurality of pads with said second plurality of pads; and a seal member sealing said first semiconductor chip, said plate member and said second semiconductor chip and having a seal member side surface; wherein said plate member has a first portion covered by said first and second semiconductor chips, and a second portion protruding from said fist and second semiconductor chips and extending through said seal member to the seal member side surface whereby said plate member is exposed to an outside of said seal member.