Rigid Flex Architecture against Two Boards and a Connector
Rigid-flex architecture eliminates discrete connector failures and signal discontinuities while reducing assembly labor, justifying higher bare-board costs.
Microsectioning Coupons
Sacrificial Test Geometry
Small, dedicated circuit patterns designed on the outer borders of a production panel are routed and encased in resin to analyze the internal structure of the board. These microsectioning coupons are used to evaluate copper thickness, via alignment, and laminate integrity without destroying the actual functional boards. They are sliced and examined under a high-power microscope by quality control technicians.
The results of this analysis determine whether the entire production batch is accepted or rejected.
Quality Control Metric
Visual verification of internal layers ensures that drilled holes are centered and free of cracks. Using microsectioning coupons allows laboratories to measure the exact thickness of plated metal in through-holes. This step is essential for confirming that the boards meet high-reliability electronics assembly standards.
Destructive Analysis Process
Mechanical sawing isolates these test patterns from the main panel once the lamination and plating steps are complete. After encapsulation in epoxy, the technician grinds down the microsectioning coupons to the mid-plane of the vias to inspect the plating quality. This inspection reveals internal defects such as inner-layer separation, resin recession, and pad lifting that would otherwise remain hidden inside the board.
It represents the primary physical record of fabrication quality required by high-reliability standards.