| 摘要 |
PURPOSE:To reduce thermal distortion of semiconductor device by placing a semiconductor material with thermal expansion coefficient alphas on the inorganic insulating material with thermal expansion coefficient of alpha1 through the composite metal plate with thermal expansion coefficient of alphaM and by setting alphaM to an interim value of alpha1 and alphas. CONSTITUTION:The virtual thermal expansion coefficient alphaM is set smaller than alpha1 of alumina by integrating the Fe-Ni plates 121, 122 on both sides of Cu plate 11 through the cold rolling. Such plate is bonded to the composite metal frame 3 by the Pb-Sn solder 101 through the alumina plate 2 metallized on both sides. The element mounting part 301 of frame 3 is formed by integrating the Fe-Ni plates 321, 322 by the cold rolling on both sides of Cu plate 31, and the terminal 303 is extended from the Cu plate 31. The virtual thermal expansion coefficient alphaM of the frame 3 is set larger than alphas of Si. Values of alphaM and alpha1 can be adjusted by changing kind of metal material, composition ratio of alloy, thickness of each layer and rolling coefficient. According to this structure, these thermal expansion coefficients are set as follow, alphas<alphaM<alpha1, drop of heat radiation characteristic can be ignored for practical use and simultaneously the heat resistance cycle can also be improved. |
