Method of reflowing conductive terminals

摘要

The invention is directed to improving of a yield and reliability of a BGA type semiconductor device having ball-shaped conductive terminals. A semiconductor wafer (1a) having warped portions is supported by a plurality of pins (21), being spaced from a heated stage (20). The semiconductor wafer (1a) is heated as a whole by uniformly irradiating thermal radiation thereto by using IR heaters (45) disposed on an upper part of the semiconductor wafer (1a) and side heaters (47) facing to lateral surfaces of the semiconductor wafer (1a). This enables uniform reflowing of the conductive terminals provided on the semiconductor wafer (1a), and makes each of the conductive terminals form a uniform shape.