Sample & Method

The attachment of an IC to a flex circuit was imaged from the back side of the flex. Gating is on the level of the aluminum stiffener and die attach. Traces on the flex and die itself are not in the plane.

Result

•  The large yellow feature is the stiffener. The eight irregular red areas near the bottom of the stiffener are delaminations of    the stiffener from the flex tape.
•  The right portion of the die is disbonded, while the left side is bonded.  Note the progressive changes in color of the die    attach from left to right.