The entire process of electronic products from the production to the use of the threat of electrostatic damage. From device manufacturing to plug-in soldering, machine assembly, packaging and transportation to product application, it is under the threat of static electricity. In the entire electronic product production process, each small step in each stage, electrostatic sensitive components may be affected or damaged by static electricity, but in fact the most important and easily overlooked is the transmission and transportation of components. the process of. In this process, transportation is easily damaged by the static electricity generated by the external electric field (such as passing near high-voltage equipment, frequent worker movement, rapid vehicle movement, etc.), so the transmission and transportation process need special attention to eliminate static electricity protection to reduce damage.
Three situations can have the following effects on electronic components:
1. The component absorbs dust, changes the impedance between the lines, and affects the function and life of the component.
2. The element is inoperable (completely destroyed) due to electric field or current damage to the element insulation and conductor.
3. The component is injured due to the soft breakdown of the electric field or the overheating of the current, and although it still works, the life is impaired. In the above three cases, if the component is completely destroyed, it must be detected and eliminated in the production and quality test, with less impact. If the component is slightly damaged, it is not easy to be found in normal tests. In this case, it is often found to be damaged after repeated processing or even when it is used. Not only is the inspection difficult, but the loss is also difficult to predict. Static electricity is as harmful to electronic components as serious fire and explosion accidents.
Anti-static safety workbench:
a. The electrostatic safety workbench is a basic component of the anti-static work area. It consists of a workbench, an anti-static table mat, a wrist strap connector and a grounding wire.
b. There should be no less than two wristband joints on the anti-static mat, one for the operator and the other for the technician, the inspector or other personnel;
c. If necessary, an electrostatic fan should be equipped with an ion fan on the workbench;
d. It is not allowed to stack plastic boxes (sheets), rubber, cardboard, glass and other debris that are easy to generate static electricity on the static safety workbench. The drawings and materials should be loaded into the anti-static paper bag;
(14) Anti-static container In the process of development and production of electronic equipment, all containers for storage and turnover of ESD-sensitive devices (component bags, transfer boxes, printed board racks, component storage boxes, etc.) should have electrostatic protection performance. Metal and ordinary plastic containers are not allowed. If necessary, the tote box for storage parts should be grounded;
(15) The static eliminator should eliminate the static charge on the surface of the insulating material and should use an ion wind static eliminator;
(16) Anti-static overalls:
a. Persons entering the anti-static work area or touching ESD-sensitive devices should wear anti-static overalls, and anti-static overalls fabrics should meet the requirements of GB12014;
b. In an environment with a relative humidity greater than 50%, the anti-static overalls are allowed to use pure cotton products;
(17) Anti-static work shoes should be worn by anti-static work shoes when entering the anti-static work area or touching ESD-sensitive devices. Anti-static work shoes should comply with the relevant provisions of GB 4385. Normal shoes are generally allowed, but conductive shoe bundles or ankle straps should be used at the same time;
(18) When an ESD-transported vehicle transports an ESD-sensitive device or an integral part containing an ESD-sensitive device, a transport vehicle with anti-static properties should be used;
Electrostatic discharge may occur when there is an electrostatic potential difference, when the electrostatic strength is large enough to penetrate the object or the surface is isolated or directly in contact with these objects. Therefore, the only way to prevent any possible electrostatic discharge event from occurring is to keep all objects at equipotentiality.
