| 摘要 |
PROBLEM TO BE SOLVED: To provide a semiconductor package which is high in bonding strength to a mounting board and excellent in solder jointing reliability when the semiconductor package is mounted on a mounting board by solder joint. SOLUTION: This BGA semiconductor package 50 is equipped with two support poles 52 of shape memory alloy located at the opposed peripheral parts of an interposer board 12. The support pole 52 is extended along the underside of the interposer board 12 at a critical temperature or below, made to protrude downward from the underside of the interposer board 12, and extended at a critical temperature or above. When the semiconductor package 50 is mounted on a mounting board 28, the semiconductor package 50 is mounted on the mounting board 28 at an accurate position first and then heated in an reflow oven to melt the solder balls. While the solder balls are melted, the support poles 52 of shape memory alloy provided to the semiconductor package 50 are made to protrude and extended downward by the heat of the reflow oven. The semiconductor package is pushed up by the support poles 52, so that solder joint 54 is formed like a column or a barrel getting from constriction and becomes excellent in shape where no stress is concentrated. |
