Non-destructive testing of through silicon vias by using X-ray microscopy

Through silicon vias (TSVs) attract considerable amount of attention and activity in recent years as a main means to achieve three-dimensional (3D) integrated circuit (IC) functionality. However, the new technology poses new integration challenges as well as new testing and verification challenges. This paper presents the latest progress in TSV non-destructive testing by means of X-ray microscopy, a technique which is approved to be the method of choice for identifying metallization defects in vias. The principle of X-ray imaging system for TSV measurement is illustrated. By using commercially available X-ray microscopy tools, metallization defects in vias having a diameter of 30 μm and a depth of 160 μm can be visualized under optimized conditions.