Hazards of ESD during SMT processing
In fact, the electronic industry has been concerned about static electricity for a long time. Since 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 electrostatic protection has gradually evolved into a new marginal subject, forming modern electrostatic engineering and electrostatic protection engineering, including the principle of electrostatic charging, electrostatic discharge model, electrostatic action mechanism, electrostatic hazards and other aspects. Shielding and its associated electrostatic testing techniques have developed rapidly.
Although humans have discovered static electricity for thousands of years, for the electronics industry, electrostatic protection is far from simple as imagined. This is because:
First, the complexity of materials and items in the SMT processing patch production process:
The manufacture of electronic products will use a variety of raw materials such as semiconductors, metals, various packaging materials, circuit board substrates, chassis, bases, etc. Equipment, operating tools, operating environment, packaging containers, etc. will make the items and materials that may come into contact with electronic devices more numerous. Contact separation, friction, induction, etc. between materials will generate static electricity, and quite a few of these items use polymer insulating materials that are prone to static electricity and are difficult to eliminate. These will undoubtedly increase the risk of electrostatic damage to electronic products and static electricity. Difficulty of protection.
Second, there are many SMT processing and production links for electronic products, and the failure of any link will cause the failure of electrostatic protection:
The manufacturing process of electronic products, from semiconductor materials to final assembly, has to go through multiple links such as semiconductor manufacturing, wafer, mounting, fixing, bonding, packaging, circuit board manufacturing, SMT processing, mounting, welding, plugging, assembly, and testing. There are hundreds of processes in different manufacturers in each link, and static electricity in any link may cause damage to the device. Once the electrostatic protection of any link is insufficient, it means that there is a problem with the final product. The systematic control of static electricity in the whole process is also an important feature of electrostatic protection in the electronics industry.