Unit-Level Traceability for Automotive Customers

Automotive commodity evidence has existed in one form or another for several years. Traceability refers to exposing and tracing each constituent that comprises every sub-system during a car. Traditionally, this has been achieved with direct part marking on mechanical or electronic components, using 1D or 2D barcodes or radio-frequency identification (RFID). 

Since vehicle suspensions are costly, this process was commenced to capture the origins of complex components. Lately, manufacturing traceability has evolved from a defensive ethos of ‘minimizing recalls’ to a proactive posture of ‘compliance.’ As compliance mandates increase, so do the associated fines for non-compliance. 

The Federal Transportation Recall Enhancement, Accountability and Documentation (TREAD) Act requires vehicle manufacturers to report back to the National Highway Traffic Safety Administration (NHTSA) any excursions on the reliability of the components. As a result, manufacturers believe traceability to stay au courant gaps within the value chain to satisfy end-user safety requirements.

Semiconductor content in vehicles is on the increase, making traceability of those components increasingly important. While there's no specific traceability standard for semiconductor integrated circuits (ICs), relevant work has been done by various stakeholders within the automotive semiconductor supply chain. For instance, the only Device Traceability Task Force that emerged from the SEMI Collaborative Alliance for Semiconductor Test (CAST) has identified the necessity for device traceability through the availability chain. This includes not just the traceability of devices but also semiconductor dies, lead frames, epoxy, bond wires, and computer circuit boards.

Two key automotive application segments—advanced driver-assistance systems (ADAS) and electrification— are expected to undergo significant innovation enabling autonomous electric vehicle (AEV) programs at various automotive OEMs. Several mission-critical safety systems, including electronic stability control, lane departure warning, anti-lock brakes, adaptive control, and traction control, which may reduce the amount of traffic accidents, are parts of those efforts. 

All of those systems require complex electronic components like high-speed processors, memory, controllers, and sensors to make sure the reliability and safety of a vehicle.

However, considering the complexities of the fashionable age semiconductor supply chain, including fables design houses, foundries, integrated device manufacturers, and outsourced assembly and test (OSAT) suppliers, there's a renewed emphasis on unit-level traceability (ULT). As an OSAT partner to automotive IC suppliers, Amkor offers ULT as another benefit to our automotive assembly and test services.

The encouragement for traceability from automotive OEMs appears from either assured (field failures) concerns or pre-delivery (0 km or 0 hr) failures. Consistent with a guarantee report, over the last five years, the car companies were paying $40 billion annually in claims. Further, estimates from a number one European OEM suggest that for each $1 of warranty costs, nearly four cents are often attributed to the failures of semiconductors. While the financial impact is obvious, recalls also end in reputation loss to OEMs also as component suppliers and puts significant stress on supply chain management.

In the aftermath of a guarantee problem, the chip supplier embarks on an eight disciplines (8D) problem-solving effort to seek out the basis cause and devise a short-term fix and a long-term solution. Generally, OEMs need an 8D report within 10 days, especially if the loss is safety-related. If it’s associated with a semiconductor component, ULT can help quickly pinpoint the origins of the failed components. For ULT to be effective, manual processes must get replaced with automated ones capturing, storing, and managing information automatically. While there's a high demand for traceability, the most important challenge remains in identifying the protocols for manufacturing data across the availability chain. Formatting such diverse data sets and subsequent communication to all or any stakeholders is challenging.

ULT provides information from an assembled IC, employing a 2D barcode marked on top of the device, as shown in Figure 1. The info includes information like wafer identification, die position, substrate or lead frame information and equipment utilized in the method. A modified assembly process flow may include additional 2D laser mark on the lead frame, automated optical inspection (AOI), and open-short testing for robust control. During this approach, one hundred pc manual optical inspections has been replaced with AOI. Because the package moves along the assembly, a 2D barcode reader verifies whether the strips are within the correct lot. Supported processing information from each step, final 2D barcodes is laser marked on top of the package. ULT services not only include data collection of processes, materials, and equipment history but also real-time retrieval and transmission.

For automotive customers, the ULT data retention is a minimum of 15 years compared to 5 years for commercial customers. Further, the advantages of ULT aren't just limited to providing traceability in manufacturing operations but also shortening development cycles. Data like strip map, wafer map, bill of materials, and therefore the resulting assembly and test yields, are often wont to shorten engineering data turns via data analytics. Such a ULT system ensures that the merchandise meets ‘zero defect’ quality standards while providing real-time access to the manufacturing information with the last word goals of increased customer satisfaction and meeting compliance mandates.