Practical ESD management specifications
1. Purpose: To prevent semiconductor products from being damaged by electrostatic discharge during production, handling, storage, and packaging, this procedure is formulated
2. Scope of application: suitable for electronics production, military industry, aerospace and other enterprises.
3. Responsibility:
3.1 All personnel in the electrostatic protection area must implement the requirements of this procedure.
3.2 The manufacturing manager/supervisor/engineer at all levels should ensure that all personnel in the department have received appropriate ESD training, and all equipment and materials have been properly ESD protected. The personnel of the Quality Assurance Department should regularly audit all electrostatic protection areas to ensure the implementation of this procedure.
4. Definition:
4.1 ESD ELECTROSTATIC DISCHARGE Electrostatic discharge, the discharge current between two objects of unequal potential caused by an electrostatic field.
4.2 The ESD protection area is equipped with sufficient ESD protection materials and equipment to prevent the production and storage areas that limit ESD damage. The following areas of the company are ESD protection areas: production workshop (POWER\MOTHERBOARD(DIP SMT)/SYSTEM), QA test Room (IQC/BURN IN ROME), material warehouse, manufacturing and maintenance department.
4.3 ESD protective materials have one or more of the following materials: 1) Limit the generation of static electricity; 2) The static charge accumulated on it quickly dissipates; 3) Electrostatic shielding. Electrostatic protection materials are divided into: according to their surface resistance: Conductive materials (<10E5Ω), static dissipative materials (10E5Ω-10E9Ω) and antistatic materials (10E9Ω-10E14Ω).
4.4 ESDS ELECTROSTATIC DISCHARGE SENSITIVE electrostatic discharge sensitivity, the product quality is reduced due to electrostatic discharge.
4.5 FACILITY GROUND refers to a piece of metal conductor buried underground, which is the convergence point of the ground wire network of the whole plant, and all ground wires of the whole plant should be directly or indirectly connected to it.
4.6 Hard Ground Connect with FACILITY GROUND directly or through a small resistor.
4.7 Soft grounding Connect with FACILITY GROUND through a large enough resistance so that the current caused by ESD is not more than 5MA.
5. Electrostatic protection tools: grounding copper block, grounding resistance, grounding wire, electrostatic ring, electrostatic clothing, electrostatic shoes, electrostatic ring inspection instrument, grounding copper braid, electrostatic shoes. Inspection instrument.
6. Program content:
6.1 All workbenches, carts, shelves, and machine anti-static floors in the ESD protection area are reliably grounded.
6.1.1 The surface board on the workbench is soft grounded by connecting to the FACILITY GROUNG through a 1M resistor.
6.1.2 The anti-static shelf should be soft grounded, and the grounding resistance should be between 1M-10MΩ resistance.
6.1.3 The anti-static cart should be in contact with the conductive floor through a copper braid, conductive wheel or conductive chain.
6.1.4 The anti-static floor should be inspected by the factory every six months. Its surface resistance is between 1M-10MΩ to ensure its anti-static effect.
6.1.5 All machines should be powered or grounded reliably. At the same time, there should be ESD monitoring measures on the machines so that the operators can take ESD protection when operating the machines.
6.1.6 The operator should wear an electrostatic ring to achieve soft grounding. It must be ensured that the electrostatic ring is in contact with the skin. All personnel in the electrostatic protection area should pass the electrostatic ring inspection. The resistance of the electrostatic ring itself should be between 200K-5M, and the resistance between the hand and the plug should be less than 100M when worn.
6.1.7 People who enter the electrostatic protection area must wear electrostatic clothing, electrostatic shoes (or shoe covers), the buttons of the electrostatic clothing should be fastened, and the electrostatic clothing should be kept in contact with the wrist.
6.1.8 Every quarter, the person in charge of ESD protection in each area should conduct a **check on the grounding status of all machines, workbenches, shelves, and carts, and then use them only after passing it.
6.1.9 For recycling boxes, scrap every 4 months, and every third month, 5 of them will be randomly tested and sent to QA for inspection. If they fail, they will be scrapped immediately to prevent static electricity.
6.2 Operation
In the process of product assembly, testing, visual inspection, analysis, and stability testing, if the product is placed in an electrostatic shielded outer packaging box, its placement and pick-up method are not restricted.
6.2.1 Products should be placed on reliable grounded workbenches, carts, shelves and machines.
6.2.2 The operator should wear an electrostatic ring for soft grounding.
6.2.3 There is no such restriction for obsolete devices.
6.3 Logo:
6.3.1 The ESD protection area should be affixed with a special ESD label to remind the operator. The ESD label should have the signature of the inspector and the inspection date.
6.3.2 The warning words of ESDS should be printed on the shipping box or a special ESD label should be affixed.
*** The product should be packed in a container when it is stored or transported to a non-ESD protected area. The container should have at least one conductive layer to shield the electrostatic field.
6.5 All personnel who come into contact with ESD sensitive materials should be trained in ESD courses.