| 摘要 |
PURPOSE:To improve the reliabilities of the mechanical and electrical connections of bumps, by reducing further the thermal stresses of the bumps. CONSTITUTION:On a circuit board 13 whereon a semiconductor chip 12 is mounted by solder bumps 15, an interposing structure 17 made of the material having a nearly equal linear expansion coefficient to the solder bumps 15 whose height is nearly equal to the solder bumps 15 is so provided as to surround the mounting part of the semiconductor chip 12. Concurrently with this, sealing is so performed with a sealing material 18 that the semiconductor chip 12 and the interposing structure 17 are covered therewith. Thereby, the semiconductor chip 12 is fixed on the circuit board 13 by the sealing material 18. In this case, the sealing material 18 does not be in the state wherein it is contacted directly with the solder bumps 15, and the chip 12 is fixed on the circuit board 13 via the interposing structure 17 having the nearly equal linear expansion coefficient to the solder bumps 15. As a result, the thermal stresses which are generated in the solder bumps 15 by repeated variations of temperature and by the difference between the linear expansion coefficients of the solder bump 15 and the sealing material 18 are reduced remarkably. |
