Fabrication Requirement
Qualification criteria for flexible and rigid flex printed circuits establish the acceptable limits for defects and workmanship during the build process. As part of the series for board performance, ipc-6013 defines Class 1, 2, and 3 standards based on the intended reliability of the final assembly. It details specific inspection protocols for coverlay adhesion and conductor breakage at the bend interface.
Manufacturers use it to grade boards before shipping to the end user. If a circuit shows excessive delamination in the flexible zone, it fails the inspection sequence.
Inspection Procedure
Microsection analysis involves cutting a finished board to examine the internal plating of the via holes under magnification. When checking against ipc-6013 criteria, inspectors look for cracks in the copper where it transitions from a rigid section into a flexible region. Misalignment of holes must stay within the specified annular ring thresholds.
The bond strength between layers is tested through pull trials. These checks verify the integrity of the lamination process.
Qualification Class
Choosing between class types determines how strictly the fabricator must evaluate cosmetic vs structural flaws. Rigid flex designs governed by ipc-6013 typically require higher standards for aerospace or medical deployment. Minimal defects are allowed in high consequence systems where repair is impossible.
For consumer electronics, minor flaws might be permitted if they do not impact the lifespan. The standard clarifies what needs to be recorded in the test report for every batch.
