Structural investigations and indentation testing of aluminium bondpads

In addition to process parameters and wire properties, also bond pad properties influence the reliability of wire bonding. Particullarly, the bondability is affected by oxide films of varying thickness at the alumina surface. The structural properties of these layers can be investigated by electron microscopy and scanning force microscopy. Oxide films with different thicknesses result also in different deformation properties of the alumina which was demonstrated by microindentation testing.