Most small joints are invisible to other inspection techniques due to their location and packaging within larger components or structures. The small spot size and high magnification of modern X-ray systems allows high resolution images of a wide range of materials to be produced allowing fault finding, optimisation of processes and inspection for quality control to be made easier. Features as small as 10 microns can be identified. An example of using X-ray for small joints is in the inspection of solder joints such as Ball Grid Arrays; here the interconnects are positioned in close proximity beneath the component making them difficult to examine with most optical inspection systems. X-ray allows the quality, quantity and alignment of the solder ball connections to become immediately visible, measurements can also be taken to ensure the pitch and size is correct.
Other areas where X-rays have proved successful is in the identification of:
- Shorting between joints.
- Porosity in die attach materials, braze and solder joints.
- Structural defects in ceramics.
- Deformed, lifted, mis-aligned and missing gold and copper wirebonds.
- Flip chip mis-alignment.
- Cracks in spot and seam welds.
For more information, please contact us.