Methods for fabricating a bonding pad having improved adhesion to an underlying structure

摘要

An insulating layer having an irregular upper surface is provided to improve the adhesion and increase the coefficient of friction between the insulating layer and a bonding pad formed over the insulating layer. By making the upper surface of the insulating layer irregular, the area of contact between the bonding pad and the insulating layer is increased. As a result, the adhesion between the bonding pad and the insulating layer is also increased. This prevents the bonding pad from being detached from the insulating layer when a bonding wire is later attached to the bonding pad. The upper surface of the insulating layer can be made irregular by etching one or more cavities in the upper surface of the insulating layer. The upper surface of the insulating layer can alternatively be made irregular by forming one or more raised structures beneath the insulating layer. The raised structures cause plateaus to be formed at the upper surface of the insulating layer.