Four major damage characteristics of static electricity to electronic products
There are three basic physical properties of static electricity: 1. Attraction or repulsion 2. There is a potential difference with the earth 3. A discharge current is generated.
These three properties can have four effects on electronic components:
1. Electrostatic adsorption of dust, reducing the insulation resistance of components (shortening life).
2. Electrostatic discharge damage, so that the components are damaged and cannot work (completely destroyed).
3. The heat generated by the electrostatic discharge electric field or current can damage the components (potential damage).
4. The electromagnetic field generated by electrostatic discharge has a large amplitude (up to several hundred volts/meter) and a very wide spectrum (from tens of megabytes to several gigabytes), causing interference or even damage to electronic devices (electromagnetic interference).
If all the components are damaged, they can be detected and eliminated in production and testing, and the impact is small; if the components are slightly damaged, it is not easy to find under normal testing. In this case, it is often found to be damaged after multiple layers of processing, and it is not only difficult to inspect, but also difficult to predict the loss. It takes a lot of manpower and financial resources to find out all the problems. And if the failure is only detected during use, the loss may be huge.
What are the characteristics of electrostatic damage to electronic products?
1. Concealment
The human body cannot directly sense static electricity unless an electrostatic discharge occurs. However, the human body may not feel electric shock when electrostatic discharge occurs. This is because the electrostatic discharge voltage perceived by the human body is 2-3KV, so static electricity is concealed.
2. Potential
The performance of some electronic components is not significantly reduced after electrostatic damage, but multiple cumulative discharges will cause internal damage to the device and cause hidden dangers. Therefore, static electricity has the potential to damage the device.
3. Randomness
Under what circumstances will electronic components be damaged by static electricity? It can be said that after a component is generated, until it is damaged, all processes are threatened by static electricity, and the generation of these static electricity is also random, and its damage is also randomness.
4. Complexity
The failure analysis of electrostatic discharge damage is time-consuming, labor-intensive, and expensive due to the fine, delicate, and tiny structural characteristics of electronic products. It requires high technology, and often requires the use of high-precision instruments such as scanning electron microscopes. Even so, some electrostatic damage phenomena are difficult to distinguish from damage caused by other reasons, which makes people mistakenly regard the failure of electrostatic damage as other failures. This is often attributed to early failure or unexplained failure before ESD damage is fully understood, thereby unconsciously masking the true cause of the failure. Therefore, the analysis of electrostatic damage to electronic devices is complicated.