Nondestructive evaluation of TAB bonding by means of acoustic microscopy: overview of progress using C-mode scanning acoustic microscopy

The authors provide an overview of past studies as well as work in progress relating to tape automated bonding (TAB). A study has been completed for the US Air Force to develop a method for nondestructive inspection of TAB bonds using SLAM (scanning laser acoustic microscopy). Another acoustic microscopy technique, the C-SAM (C-mode scanning acoustic microscope), works in a reflection mode (pulse echo) and can be used to gain single-sided access to the outer lead bond interfaces. The studies included work performed on outer lead bonding to ceramic substrates so that both acoustic microscopy techniques could be used on the same samples. With the information derived, evaluation of the outer lead bonding to composite boards using the C-SAM was performed as well. Also, investigations of TAB inner lead bonding using the C-SAM technique are presented