How can semiconductor manufacturing technology alleviate the problem of electronic component obsolescence?

When assessing the long-term supply risk posed by product selection, it is important to be aware that the part number information provided by the original component manufacturer (OCM) covers far more than the Bill of Materials (BOM) health report provided by commercial tools.

If the chip is regarded as a complete "puzzle" painting, this "puzzle" painting is composed of many small "puzzle pieces", each small "puzzle piece" is crucial, and once there is a problem, it may cause the entire product to be obsolete. These "jigsaw pieces" are diverse and cover various sub-parts of the semiconductor product from business revenue, such as foundry technology, packaging methods, substrate or lead frame selection, test platform and design resources.

In addition, these "jigsaw pieces" also include the semiconductor company's overall strategic direction or market focus. Over time, the market focus of semiconductor companies may change, but those systems companies with long-term cooperation (such as customers), their product focus may not change easily. Therefore, when assessing the long-term supply risk posed by product selection, it is important to be aware that the part number information provided by the original component manufacturer (OCM) covers much more than the Bill of Materials (BOM) health report provided by the commercial tool can cover.

How does the manufacturing supply chain affect the long-term availability of products?
Most traditional semiconductor products are packaged in lead frame form, such as DIP, PLCC, QFP and PGA. Today's semiconductor market has moved away from leadframe packaging as the primary yield driver, and is increasingly moving toward substrate based assembly.
· Why the industry is gradually abandoning lead frame assembly
To deeply understand the reasons for the gradual disappearance of lead frame components, we need to conduct a comprehensive study from the history of the assembly base, the change of profit margins, and the development trend of the industry.
As early as the 1980s, the trend of offshoring has quietly emerged. At the time, TSMC had yet to make a name for itself in the semiconductor industry with its superior foundry technology. Overseas assembly was mainly driven by cost factors, but also by environmental constraints, because the assembly process was not as clean as it is now. With the increasingly fierce competition in the industry, many lead frame suppliers are gradually eliminated in the competition, only those who are the largest suppliers can barely maintain profitability. Today, lead frame margins have fallen into the single digits, while most semiconductor companies have margins closer to 50%.
In the 1990s and early 2000s, the production of lead frame components reached an all-time high, driven by high-speed IO(input/output) and BGA(welded ball array package) assembly. However, with the advent of high-speed IO standards (such as PCI-e, multi-Gigabit Ethernet, SATA, SAS, etc.), we have found that traditional lead bonding technology has become a key factor limiting device performance - high-speed IO standards and other new standards have established a clear performance roadmap, but lead bonding technology is difficult to meet these performance requirements.
At the same time, with the substantial increase in device speed, its power consumption is also increasing. Lead bonding distributes power from the outside of the chip to the core, but for high-performance products that became widespread in the 1990s, power from the outside of the chip alone cannot meet the growing demand for power.
To solve this challenge, flip chips and BGA package substrates have emerged, which effectively alleviate the power distribution challenge by providing power directly to the core, eliminating the dependence on lead bonding. This solution not only improves power transmission efficiency, but also achieves better signal integrity, enabling the device to meet the requirements of the high-speed SerDes (serializer/deserializer) standard.
In the early 21st century, as the output of lead frame components gradually decreased, a new type of low-pin number package - QFN package began to emerge. QFN packaging is a baseboard-based assembly that uses lead bonding technology to connect the chip to the lead. The emergence of this packaging method indicates that semiconductor packaging technology is developing in a more efficient and advanced direction.
Today, the output of substrate components has far exceeded that of lead frame components. Previously, trimming and molding tools were the most expensive lead frame processing equipment for packaging plants. As the production of lead frame components shrinks, substrate based assembly methods become mainstream. Packaging plants switch from lead frame assembly to substrate assembly, requiring the replacement of trimming and molding tools, and their profitability is only in the single digits, which is difficult to support the complete abandonment of lead frame components.
The industry chose to abandon lead frame components because of the technical performance requirements for neutral bonding and the high cost of continuing to produce low-volume lead frame components. This is not only due to economic considerations, but also the inevitable result of technological progress.
Once the assembly plan is determined, the test plan must be adjusted soon after. We pay close attention to similar developments in test technology to ensure a smooth transition to substrate assembly testing. If there is a non-connection problem in the substrate assembly test, it may lead to the emergence of technical backwardness. At present, the latest production test equipment on the market mainly serves the assembly based on the substrate, and all measures aimed at reducing the cost of mass production are mainly around the substrate components.
However, it is worth noting that as production volumes are gradually reduced, OSAT(outsourced semiconductor packaging and testing) plants face increasing challenges in testing for small series production. This challenge is particularly evident in products that are based on lead frames.