US Patent 7247945 Semiconductor apparatus

A semiconductor apparatus includes a printed circuit board, a peripheral type first semiconductor package which has a first group of ball electrodes arranged in a peripheral type first arrangement area and a first group of additional ball electrodes arranged inside the first arrangement area and which is arranged on a first surface of the printed circuit board, and a peripheral type second semiconductor package which has a second group of ball electrodes arranged in a second arrangement area and a second group of additional ball electrodes arranged inside the second arrangement area and which is arranged on a second surface of the printed circuit board. A ball electrode located at at least one corner of the first group of ball electrodes is arranged at a position to oppose a corner of the second arrangement area, and at least one ball electrode of the second group of ball electrodes is arranged at a position to oppose the second group of additional ball electrodes through the printed circuit board.