Discussion on the Current Status of Chip Failure Analysis

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Discussion on the Current Status of Chip Failure Analysis [Copy link]

Failure analysis is to analyze damaged products to provide materials for improving design or clarifying responsibilities. However, from the perspective of the industry, many companies, especially small and medium-sized companies, do not do failure analysis well. There is a Chinese saying: "One failure makes you wiser", and there is also a saying in "The Analects of Confucius" that "Do not make the same mistake twice". The essence of this is to learn from failure and avoid further mistakes.

On the one hand, some small and medium-sized electronic product manufacturers do not have a good material control system and cannot effectively trace materials. Once a problem occurs, it is difficult to find the channel and source of the year. Even the authenticity of the materials cannot be guaranteed. What's more, some companies have no concept of failure analysis and remain in the state of firefighting when they are broken. There is no question of learning lessons from the root. Some companies always break a chip when they use it, and they think that the chip quality is poor, but they do not analyze the cause of the damage from the root and draw conclusions blindly. As a result, the chip of another manufacturer is still broken. Many years later, they found that their own circuit lacked protection design.

On the other hand, almost all electronic component manufacturers take an evasive attitude when facing failed products. For international first-line brands, the general process is to provide failed samples first, then fill out questionnaires, and then send them to the global failure analysis center for analysis. As a result, a failure analysis often takes 1 to 2 months. And the report obtained often says that the user used it improperly. For example, static electricity is not well protected, and moisture-sensitive devices have popcorn effects. It seems that there has never been any responsibility for electronic component manufacturers. In fact, for many devices, especially some newly launched special chips, there are often many bugs when they first enter the market, and these bugs will cause failures of one kind or another. These bugs are concealed by electronic component manufacturers.

Moreover, for many small and medium-sized enterprises, if they have many channels for purchasing goods, they are often rejected by the original manufacturer at the first stage. Generally speaking, the original manufacturer requires the agent to provide the sample of the expired sample. As a result, the new agent checks the batch number and says that the goods are not purchased by me, so I cannot send samples. The original supplier says, you don’t buy my goods anymore, why should I send you samples. As a result, many small and medium-sized enterprises’ goods are damaged without knowing why.

Maybe you will ask, aren't there professional failure analysis companies? Yes, there are many companies doing failure analysis of electronic components, but the quality varies. A common phenomenon is the lack of the ability to analyze the failure mechanism in depth. Many companies only use high-precision equipment to find the failure point, but they often cannot provide in-depth help on why the failure occurs, how to avoid it, and who is responsible.

Therefore, enterprises need to have certain failure analysis capabilities. There are also issues that need attention. One is the equipment of instruments, and the other is the staffing. Advanced failure analysis instruments are often expensive, and instruments such as scanning electron microscopes are worth millions. For general enterprises, they often do not have the strength to equip a full set of instruments and equipment. On the other hand, even if these instruments and equipment are equipped, the operation of the instruments, the interpretation of the results, and the inference of the mechanism all require highly qualified failure analysts. It is difficult for general enterprises to be equipped with complete equipment and expert personnel. This is the embarrassing status quo of failure analysis.

However, difficult to do does not mean impossible to do. For most companies, it is necessary to equip and train their own failure analysis team according to their own strength. General companies can first equip a transistor tracer for failure analysis. The better domestic products only cost tens of thousands of yuan. It is much more convenient to train people in this field on one instrument than to roll out the whole system. The transistor tracer can basically locate the failed device to the failed pin. If the conditions are good, it can also be confirmed whether it is electrical overstress damage or electrostatic damage. Knowing these two points can help developers check the design, and if it is electrostatic damage, the protection conditions for production use can be improved.

If you want to conduct further analysis, you need to build a metallographic analysis laboratory. The equipment required is: metallographic microscope, stereo microscope, cutter, grinder and polisher, and consumables for sample preparation. If you have such a laboratory, in addition to being able to see the surface damage of various components, you can also observe the internal conditions by making slices. Moreover, at this level, the laboratory can not only be used for failure analysis of components, but also for inspection of welding assembly process failures, such as checking welding conditions, the formation of intermetallic compounds, etc. At this time, it can also be used for the initial certification of components and destructive physical analysis.

At this stage, the investment is basically large. If a full set of imported equipment is used, the total price will be at least RMB 60-90. If domestic equipment is used, the investment can be much less. Using a full set of domestic equipment, it can basically be completed within RMB 100,000. At this time, in terms of personnel quality, people who understand electronic component material science and semiconductor physics are needed to carry out related work.

For integrated circuits, many failures occur in the bonding system, that is, the connection between the pins and the integrated circuit chip. The metallographic sectioning method often destroys the chip's bonding system. At this time, an opener may be used to open the plastic material on the surface of the integrated circuit. For many companies, this thing is too expensive. It often costs tens of thousands of dollars. And expensive consumables such as nozzles must be replaced frequently, so many companies simply don't buy this thing and use manual opening methods. You can even see videos of foreigners doing this on youtube. However, strong acid is required for opening, and some chemicals are still state-controlled drugs and need to be registered with the public security bureau. In addition, in actual implementation, whether it is an opener or manual opening, it needs to be carried out in a ventilated kitchen. Take good personal protection. For personnel, in addition to the above knowledge, if you want to use highly corrosive chemicals, in principle, you must have a "hazardous chemical operation permit."

Generally, enterprises can achieve this level. If the above analysis still cannot be concluded, you can go to a failure analysis company in the society or to a university to rent their equipment for analysis. If you suspect that there is a problem with the incoming materials and identify the batch failure, you must go to a laboratory with IEC 17025 certification for third-party analysis and identification. The report they issue is legally binding.

If a company wants to become a century-old company, it must have high-quality products. Failure analysis is an important means to discover quality problems and is of great significance to improving quality. I hope our failure analysis will no longer be embarrassing.

Fortunately, as people pay more attention to quality and reliability, various enterprises and institutions have also paid more attention to failure analysis in recent years. The state has also introduced and implemented a variety of support policies for the semiconductor industry. In addition to the introduction and learning of advanced foreign technologies, Taiwanese engineers and technology have opened laboratories in the mainland to boost the mainland's analysis capabilities. The quality of analysis has been greatly improved by the accumulation of third-party laboratory equipment and years of failure analysis experience and technology . I believe that failure analysis will soon no longer be embarrassing.

led2015

In the past, when using chips as power supplies, there would always be a situation where the power supply voltage surge would blow up the chip, and sometimes formula calculations are not omnipotent.

qwqwqw2088

This kind of analysis is very

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