Application of the pressure wave propagation method for adhesion defects detection in very thin multilayer structures

The application of pressure wave propagation (PWP) method for adhesion defects detection in very thin multilayer structures was discussed. The test of trilayer structure and preliminary measurement of the acoustical and electrical properties was also described. By analyzing the signals assesses the correctness of the signal in the time domain, it was possible to determine at which interface the disbonds occurred. It was to be possible to detect and localize in trilayer structures, submicron gaps and a percentage of totally disbonded area as follows as 10% in the tested zones.