Inspecting Your Order: What to Look for in JLC’s X-Ray Reports

The JLC X-ray inspection provides verification for the solder joint integrity of hidden solder joints (especially on BGAs and QFNs). Key items to review on JLC X-ray reports are ball alignment, void percentage, and bridges between the pads. Voids should typically be less than ~25% to provide an acceptable level of reliability in most uses. Verify the even distribution of solder and proper wetting across all joints. Issues with alignment or excessive amounts of voiding may indicate issues with the solder paste reflow profile or stencil. Additionally, verify that all expected solder joints are accounted for, as missing solder joint connections can happen through not enough solder paste. X-ray is used in conjunction with AOI; therefore, you should check both prior to issuing acceptance of a board. Identifying issues at this early stage helps avoid expensive failure in the field.