US Patent 7550322 Manufacturing method for resin sealed semiconductor device

A semiconductor device manufacturing method comprises etching a front side of a conductive board to form plural sets of a die pad portion and bonding areas, each set corresponding to one semiconductor device. Semiconductor chips are mounted on respective ones of the die pad portions using conductive paste. Electrodes of the respective semiconductor chips are electrically connected with metal wires to the bonding areas, and then the front side of the conductive board, including the semiconductor chips, the bonding areas and the metal wires, are sealed with a molding resin to form a resin-sealed body. Thereafter, the back side of the conductive board is selectively removed, such as by etching, to leave the die pad portions and the bonding areas protruding from a bottom surface of the resin-sealed body. Then the resin-sealed body is separated into individual semiconductor devices.