What causes the failure of semiconductor components? Be sure to consider these 5 points!

Date：2022-06-09 17:40:35Views：804

With the development of science and technology, especially the upgrading of electronic technology, the quality requirements for the components used in electronic equipment are becoming higher and higher. With the wide use of semiconductor devices, their service life is degraded and eventually leads to failure. A large part of electronic components work under extreme temperature and harsh environment, which makes them unable to work normally, and a large part of components stop in laboratories and wafer factories during R & D. In addition, improper use, surge and electrostatic breakdown are all the reasons that lead to the shortening of the service life of semiconductor devices. In addition, some devices that operate normally are also damaged, resulting in the degradation of components.

There are countless reasons for the failure of semiconductor components, mainly in several aspects:

1. design of components

Chip aging is an increasingly serious problem in advanced feature size nodes, but so far, most design teams have no need to deal with it. With the new reliability requirements put forward in the automobile and other markets, these factors that affect aging need to be comprehensively analyzed, which will change significantly.

It is generally known that semiconductor devices will gradually age over time, but people do not know the aging mechanism or the constraints that lead to chip failure. In addition, according to different applications, there are certain requirements for the shortest service life of devices.

It may be 2 or 3 years for consumer equipment and 10 years for telecom equipment. In view of the complexity of aging process and it is usually difficult to fully predict, nowadays many chip designs often adopt redundant design methods to ensure sufficient margin to meet the requirements of reliable life.

Operational amplifiers, for example, are the foundation of many things. The op amp must be properly biased and must have some margin in the overdrive voltage. It must then be ensured that sufficient margin is left so that the aging of the operational amplifier will remain within the saturation region of the transistor over time. The overdrive margin of the transistor is shrinking because the 7Nm power supply voltage is 750mv and the threshold is about 350mV, so there is almost no room to reserve a large margin. With aging, the threshold voltage can be shifted by up to 50mV. If the bias circuit of the operational amplifier is shifted by 50mV, it may change from a saturated region to a linear region or a triode region, and the transistor will become a resistor without gain. The function of the operational amplifier is to provide gain, when the circuit becomes useless.

Aging and reliability are challenges facing simulation designers. Today's designs may not run tomorrow, because these designs may be degraded. At present, the most important thing is to ensure that all aging and reliability requirements of the market are met.

2. manufacturing of components

The manufacture of semiconductor devices involves measuring structures only a few nanometers. As a reference, the diameter of human DNA strand is 2.5nm, while the diameter of human hair is 80000 to 100000nm. A single grain of dust can destroy several bare wafers on a wafer.

If the die size becomes larger, the probability of random failure will increase. For mature process nodes, the yield may be between 80% and 90%. However, for newer nodes, the yield may be much lower than 50%, although the actual number is strictly confidential.

Even if the bare chip is not catastrophic, it cannot be considered operable. If the manufacturing steps are not perfect, even the process changes of one atom will produce significant differences. Although this may not affect some parts of the design, if the process change happens to coincide with the critical timing path, the device may not meet the specification.

With the design gradually evolving into deep submicron technology using advanced packaging, the existing simulation tools and design methods can not well reflect the changes and their impact on reliability. This can lead to loopholes in the design process, leading to some failures. Design processes increasingly allow changes to be considered early in development to minimize their impact, while design techniques such as redundancy can reduce the number of nearly operational chips that need to be discarded.

3.esd protection

Generally, the chip will include ESD protection. If 0.5V voltage is applied to the outside of the chip, an electric field of 0.5mv/m will be generated on the 1nm medium. This is sufficient to cause a high voltage arc. For a single die in the package, their goal is a standard such as 2kJ.

If you try to minimize ESD, or even eliminate it on these wide i/o interfaces or any type of multichip interface channel, it means that you cannot really test each chip according to the same standard for a single chip. They must be more professionally tested because they have little or no ESD protection.

ESD events can cause problems even during operation. ESD can cause many types of soft errors in portable electronic products. During ESD events, noise may be caused on the power supply network (PDN) due to the sensitivity of some ICs (oscillator IC, CPU and other ICs) or the field coupling of the PDN.

4. influence of magnetic field on semiconductor

With the multifunction of smart phone and tablet computer terminals, the required power supply voltage also involves a variety of specifications. Therefore, the number of inductors used in power circuit is increasing. Integrated inductors for power circuits are required to be small in size and support high current, and low in loss in some battery devices such as smart phones.

An inductance stores energy in a magnetic field to perform its function. However, the inductance is affected not only by the electromagnetic energy generated by itself, but also by the external magnetic flux. Ensure that the inductance value of components refers to the value without external magnetic flux. Therefore, when the inductor is packaged in the presence of external magnetic flux, it may not play its due role.

Therefore, EMS is a new problem that people have to worry about. The energy injection test is to inject 1W energy from 150kHz to 1GHz. At each frequency, 1W of energy is injected into the system. If there is not enough protection, it will enter the internal circuit of the chip along the path to cause damage, or the voltage on the pin may be too high. If the voltage is too high, it will produce over-current strain.

5. switching power supply

Now the power supply industry has come out of the market downturn of the previous threeorfour years, but the competition in the switching power supply market is becoming increasingly fierce. China's power supply enterprises have no advantage in the world market only relying on low-cost manufacturing. At the same time, the position of foreign power semiconductor suppliers in the power supply industry has been further strengthened.

Although the market development situation is optimistic, over the past decade, Chinese switching power supply enterprises have relied on low-cost advantages to produce products that meet the quality and performance parameters requirements of world-renowned OEM enterprises. In order to achieve success, Chinese power supply enterprises have invested in many links. More and more semiconductor manufacturers have adopted embedded power supplies to reduce product costs, which has also led to higher and higher power.

The higher the power, the higher the heating of electronic components. The problem caused by heating is not only that the mobile phone becomes hot in the pocket. It will lead to the degradation of transistors and their connections, which will directly affect the performance and reliability of semiconductor components.

The chip runs in a harsh environment and still faces great challenges in the product life cycle. However, as the manufacturing size becomes smaller and new packaging technologies are adopted, new impacts will occur, which directly leads to the failure of device performance research and development.

The above is related to the failure of semiconductor components compiled by the core detection team. I hope it can help you. Shenzhen Chuangxin Online Testing Technology Co., Ltd. is a well-known professional testing institution for electronic components in China, with 3 standardized laboratories covering an area of more than 1000 square meters. The scope of testing services covers: testing and verification of electronic components, IC authenticity identification, material selection for product design, failure analysis, function testing, factory incoming material inspection, X-ray testing of components and parts, tape braiding and other testing items.