During production, we should pay more attention to static electricity.
Static electricity is an objective natural phenomenon, generated in many ways, such as contact, friction, and current flow. Its basic process can be summarized as: contact → charge → transfer → formation of an electric double layer → charge separation.
Static electricity on equipment or the human body can reach tens of thousands to hundreds of thousands of volts, and even under normal operating conditions, it often reaches hundreds to thousands of volts. Due to their own movements and contact/separation, friction, or induction with other objects, the human body can carry several thousand or even tens of thousands of volts of static electricity. Static electricity is the result of an imbalance of positive and negative charges in a localized area. It is a form of electrical energy that remains on the surface of objects, characterized by high potential, low charge, small current, and short duration.
The main measures for static electricity control include: static leakage and dissipation, static neutralization, static shielding and grounding, and humidification.
Component breakdown damage caused by electrostatic discharge is the most common and serious static electricity hazard in the electronics industry. It is divided into hard breakdown and soft breakdown. Hard breakdown is a one-time event causing dielectric breakdown, burnout, or permanent failure of components; soft breakdown, on the other hand, causes performance degradation or a decrease in parameter indicators.
During the production process, the transfer and storage of electrostatic sensitive components and printed circuit boards between processes must utilize anti-static loading boxes, component boxes, turnover boxes, and turnover pallets to prevent damage caused by static electricity accumulation. When packaging finished products, anti-static shielding bags, packaging bags, boxes, and crates must be used to avoid static damage during transportation.
During the production of electronic products, components and finished products frequently come into contact with, separate from, and rub against equipment and tools, generating static electricity. Anti-static cushions, turnover carts, repair kits, tools, and work chairs must be used, and proper grounding must be implemented to ensure rapid discharge of static electricity.
Frictional charging and static electricity from the human body are two major sources of hazard in the electronics and microelectronics industries. However, the generation of static electricity is not the main hazard; the hazard lies in the accumulation of static electricity and the resulting electrostatic discharge. Charged objects create electrostatic fields around them, producing mechanical effects, discharge effects, and electrostatic induction effects, which must therefore be controlled.
Due to the mechanical effects of static electricity, airborne dust particles can adhere to components such as silicon wafers, severely affecting the quality of electronic products. Therefore, anti-static measures must be taken in cleanrooms. The walls, ceilings, and floors of cleanrooms should be made of anti-static, dust-free materials, and a series of anti-static protection measures should be implemented for operators, workpieces, and equipment.