| 摘要 |
PURPOSE:To prevent the disconnection in a portion where a gold lead is bonded to an aluminium, by forming a corrosion resistant alumina film on the surface portion of the aluminium pad where aluminium is exposed. CONSTITUTION:A gold lead 2 is bonded to an aluminium pad 1 at a joint 3, and PSG4 is formed therearound. This structure is dipped in pH7 pure water and the water is boiled in order to change the aluminium exposed on the surface of the aluminium pad where the lead not bonded into alumina. Since any acid contained in the water will corrode the aluminium, the pure water must be precisely controlled not to contain even the slightest quantity of acid. For this purpose, the water is controlled with respect to its pH such that the pH is maintained at 7. The package to which the lead has been bonded is dipped in this pure water and the water is boiled to 90-100 deg.C. The exposed aluminium pad portion, when dipped in this water, produces an alumina film 6 through chemical reaction. |
