Abstract: An area array type semiconductor device employing a single side wiring board in which a signal waveform is not likely to be disturbed even if a higher speed signal is applied includes more ground pads than the number of ground external terminals (ground wire land). The ground wire is formed in a larger width than the other wires on a single side of a substrate so as to form a plane, and gaps between the ground wire and the signal wire or the power wire are set to be substantially equal.

Abstract: A semiconductor device includes a tape carrier, a semiconductor chip, a metal heat spreader, a support ring, and a projection, recess, and spot welding portion. The tape carrier includes a TAB tape. The semiconductor chip is mounted on the tape carrier. The metal heat spreader is fixed to a surface of the semiconductor chip opposite to the tape carrier to dissipate heat generated in the semiconductor chip. The heat spreader has a shape larger than that of the semiconductor chip. The support ring is arranged between the heat spreader and tape carrier and is adhered to the tape carrier. The support ring serves to ensure a predetermined gap between the heat spreader and the tape carrier and to prevent warp of the tape carrier. The projection, recess, and spot welding portion bond the heat spreader and reinforcing member to each other by employing one of mechanical engagement and fusion welding. A method of manufacturing a semiconductor device is also disclosed.