What are the hazards of ESD during SMT processing?

What is ESD?

ESD is the abbreviation of electron static discharge, usually also refers to the protectionof electrostatic discharge, static protection or anti-static.

ANSI/ESDS20.20 is the standard for static protection in the SMT processing of the American Electrostatic Discharge Association. It is the most authoritative standard for electrostatic protection in the electronics industry in the world, and the only static protection standard that can be certified. The company has passed the ANSI/ESDS20.20 certification, which indicates that the static electricity has been strictly controlled in the production, thus ensuring the quality of the products and ensuring the reliability of the products.

Static electricity and electrostatic discharge are ubiquitous in our daily lives, but for electronic devices, a slight electrostatic discharge that we can't detect can cause serious damage. The rapid development of electronic technology has made electronic products more powerful and the volume smaller and smaller, but this is at the expense of the increasing electrostatic sensitivity of electronic components. This is because high integration means that the unit wiring will become narrower and narrower, and the ability to withstand electrostatic discharge is getting worse. In addition, the materials used in a large number of newly developed special devices are also electro statically sensitive materials, thus electronic components, especially semiconductor materials, are increasingly required for electrostatic control of process environments such as SMT processing, production, assembly and maintenance.

On the other hand, in the environment of electronic product SMT processing, production, use and maintenance, a large number of various polymer materials that are easy to generate static electricity are used, which undoubtedly brings more difficulties and challenges to the electrostatic protection of electronic products.

Electrostatic discharge has two kinds of injury to electronic products: sudden injury and potential injury. The so-called sudden injury refers to the device being seriously damaged and losing its function. This type of damage can usually be detected in the quality inspection of the production process, so the main cost to the factory is the cost of rework maintenance.

The potential injury refers to the partial damage of the device, the function has not been lost, and can not be found in the detection of the production process, but the use of the product will become unstable, sometimes good, sometimes bad, and thus constitute a greater hazard to product quality. Of these two types of injury, potential failures account for 90%, and sudden failures account for only 10%. That is to say, 90% of the electrostatic damage is not detected, and will only be discovered when it is used by the user. Most of the problems such as frequent crashes, automatic shutdown, poor voice quality, loud noise, signal sometimes good sometimes bad, and key error occur in mobile phones are related to electrostatic damage. Because of this, electrostatic discharge is considered to be the biggest potential killer of electronic products, and electrostatic protection has become an important part of electronic product quality control. The difference in stability between domestic and foreign brands of mobile phones also basically reflects their differences in electrostatic protection and anti-static design of products.

In fact, the electronics industry has been paying attention to static electricity for a long time. From the emergence of electronic products, especially transistors, this problem has begun to be recognized and valued by enterprises and countries. The research on static electricity and static electricity protection has gradually evolved into a new edge discipline, forming modern electrostatic engineering and electrostatic protection engineering, including the principle of electrostatic electrification, electrostatic discharge model, electrostatic mechanism, electrostatic hazard and its protection and related electrostatic testing techniques have been rapidly developed.