| 摘要 |
PURPOSE:To prevent the damage at the joint of a bump electrode to a chip as well as the deterioration in the characteristics due to the permeation of atmospheric air from occurring by a method wherein the shape and size of an upper side metallic film is formed almost similar to those of a bump electrode while a lower side metallic film is formed to protrude outside from the edge of the upper side metallic film. CONSTITUTION:An upper side metallic film 6 constituting a bimetal film is filmed in almost the same shape and size as those or the bottom part of a bump electrode 7 while the lower side metallic film 5 is formed to protrude outside from the edge of the upper side metallic film 6. Accordingly, the dimension of the bimetal composed of both metallic films 5, 6 normally in different thermal expansion coefficient is contracted to reduce the degrees of inner thermal stress or warp; besides, when the bimetal film is backed with a metal 7 for the bump electrode, the inner stress of the bimetal is displaced and the warp is actually eliminated as well as any crack or damage is avoided during heating and cooling processes. Through these procedures, the troubles such as the damage at the base of the bump electrode 7 to a chip as well as the deterioration in the characteristics of a semiconductor device due to the permeation of atmospheric air from the damaged part can be prevented from occurring. |
