KGD screening for chiplet-based 2.5D/3D packages has been a multi-vendor coordination problem since CoWoS volumes started climbing. Teradyne and TEL just shipped a production-ready integrated test cell: UltraFLEXplus paired with the Prexa SDP prober. KGD is now a single coordinated step rather than a DIY integration exercise each OSAT, foundry, or fabless team solves differently.
The constraint being removed is thermal and handoff uncertainty. Leading-edge AI silicon runs at power densities that singulated die probing cannot handle without tight temperature control. TEL's Prexa SDP manages that. Teradyne's UltraFLEXplus provides the test instruments. The two are now validated together, which means customers can adopt the flow without solving the probe-to-tester integration problem themselves. The solution is open-architecture and absorbs alternate probe cards and manipulators, so it is not a closed two-vendor lock.
The gap in advanced packaging yield today is not lithography or bonding accuracy. It is the defective die that clears wafer-level test, enters a CoWoS package, and pulls down the assembled unit. KGD screening at multiple points in the packaging flow is the fix. Fabless teams taping out for 2.5D assembly who are not planning KGD gates should revisit that budget line. The cost of adding a KGD step is real. The cost of scrapping a high-value package because of a single defective die is larger.