Printed Circuit Board
In X-ray micro CT (Computed Tomography), projection images of X-rays transmitted through a very small object are reconstructed to produce a high-resolution 3D image. By displaying the reconstructed image in 2D cross-section (slices) and 3D volume renderings, the inner structure and defects in the object can be analyzed non-destructively.
NON-DESTRUCTIVE ANALYSIS BY X-RAY CT
Defective site analysis of LED package by CT imaging and volume rendering
The damaged LED package was subjected to X-ray micro CT utilizing a spatial volume resolution of 4 um with the image data collected over six hours. The 2D slice view provides cross-sections at arbitrary positions as if one were actually slicing the sample.
The schematic diagram of the LED chip on the PCB for LED bulb
Stepping through the 2D slices, a defective site encompassing two LED chips was found (shown by the red arrow in figure).
The figures below show volume rendering views of the reconstructed image. By displaying the 3D volume rendering, one can understand the positional relationships among the LED chips and the individual bonding wires that 2D slices are not able to display. In the rendered 3D volume, a broken bonding wire was observed. As shown in the figures below, 3D micro X-ray CT can non-destructively magnify and visualize the inner structure of micro objects. In addition to the qualitative 2D and 3D visual representations, micro CT can also be used for quantitative analysis of size and distances.