Studies of Determination Method of TiN Residue on Al Bondpads

Energy-dispersive X-ray microanalysis technique (EDX) has been widely used to determine the compositions of particles, contamination and thin film layers in wafer fabrication. However, we still face some common problems. In this paper, we will answer the question theoretically and experimentally: can we use EDX to determine TiN residue on Al bondpads? After performing theoretical and experimental studies, EDX is not recommended to determine TiN Residue on Al Bondpads with the barrier metal TiW/Ti layer due to some limitation: using lower kV could not excite Ti Ka peak and using high kV the beam penetrate to underneath barrier metal, which cause confusion of the signal detected. And then we will propose a determination method of TiN residue on Al bondpads using Auger analysis.