| 摘要 |
PURPOSE:To obtain a rigid connection even if aluminum wirings are used by controlling the thickness of an aluminum film and the diameter of a ball after bonding. CONSTITUTION:A bonding strength has a correlation with the diameter of a ball after bonding. In other words, when the logarithm 2ln(D/D0) of the value produced by dividing the diameter D0 before bonding by the diameter D of the ball after bonding is a strain, if the strain amount is increased, an area of the ball and the broken oxide film of the film boundary increases. Thus, the bonding strength increases. Accordingly, in order to obtain a connection having high reliability, the bonding may be performed by a method of increasing the strain of bonding. When the thickness of the aluminum film increases, the bonding strength increases. From the above, when the D/D0 is (y) and the thickness of the aluminum is (x), the connection having high reliability can be obtained by controlling the (x) and D so as to become the value of higher obtained by y= 3.32-0.0225x. |
