August_EDFA_Digital

edfas.org ELECTRONIC DEVICE FAILURE ANALYSIS | VOLUME 22 NO. 3 22 delamination and voids within organic layer are shown. To illustrate the ability of the system to image defects in organicmaterials a block of carbon fibers reinforced poly- mers (CFRP) is used. Finally, the capability to detect the presence or absence of a wet surface filmwithin cracks or pores in devices or porous media is demonstrated. SIP WITH PHASE CONTRAST AND DARK FIELD/SCATTERING CONTRAST IMAGING AnSIPhas several integrated circuits enclosed inoneor more chipcarrier packages that are stackedandconnected by fine wires or through metal bumps. SIP is typically used inmobile phones and digital music players. Sidewall delamination failures on advanced packages such as an SIP are one of those failure modes that currently cannot be identified nondestructivelywith conventional imaging tools, such as C-SAM or XRM. In Fig. 5, while thewires and the different layers of dies in the x-ray absorption contrast canbe observed (image on top), it is not possible todiscernanydelaminationbetween the silicon dies and the underfill. But the delamination is Fig. 6 Radiograph of sidewall delamination of SIP showing delamination in phase contrast (third image from left) and dark field imaging (image on right) but not in absorption contrast mode (second image from left). Image on left (top colored image) is an optical image showing overviewof cross section of the packagewhile the bottom image is SEMcross section showing both lateral and sidewall delamination along the chip-underfill interface. Fig. 7 Image on left is a radiograph of absorption contrast in SIP. Center image is a phase contrast radiograph where the arrow shows a bubble/void in the organic layer. The image on the right shows lateral delamination between the chip and underfill organic layer.