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The anti-static measures

The establishment of a static security zone 
In the specific manufacturing process, the establishment of static electricity safety, use of a variety of methods of control, the region will be possible to maintain voltage electricity in the most sensitive components are safe under the threshold. 
In general, a complete static safety zone, should at least include conducting effective hand bags, special grounding line, anti-static wrist strap, floor mats to the conductor (such as pieces of metal, electrical conductivity of the tape, and lead the human body, such as capacitors ) On the conduct of electrostatic discharge. Ibid, with the elimination of static electricity, and can not be used in insulation on the accumulation of charge, the charge can not flow in the insulator, can not leak out the release of grounding method. Figure 2.10 is a typical sketch of the security zone. 
Figure 2.10 typical security zone diagram 

Static security in the area, there is a very important parameter is the resistance put diarrhea static security. Although the static electricity from the region put the speed of diarrhea, Xie Fang, the smaller the better resistance, but subject to two limitations. The most important thing is to give to the work of the operators to provide anti-shock conditions, according to the human body when the shock out of the woods have the ability to limit the current (10-16mA) requirements, voltage security check 5mA calculated, 
By R = U / A 
For U = 220-380V, a R = 4.4 × 104-7.6 × 104W. R is greater than the value of taking 1.0 × 105W. 
On the other hand, if the restriction is a small resistance, diarrhea quick release, has been on a static device, the occurrence of diarrhea will put too much current devices led to the injury, but unsafe. 
Then the safety limit of resistance is determined by how it? Is a matter of seconds to decay 5000V electrostatic voltage to 100V voltage safety grounding resistance to allow the greatest value of the decision. According to the type: 
U = U0e-t/RC, 
Check U0 = 5000V, U = 100V, t = 1S, C = 200pf, available R = 1.28 × 109W. 
As a result, security in the region put the safety of diarrhea in general to ensure that the resistance is less than 109W, that is, whether it is hand bags, ground mats or wristband, as long as the resistance of the system is less than 109W, to ensure security to 1S-voltage discharge in value This greatly reduces the sensitive devices in the electrostatic damage to the next. 
According to the actual situation of different forms to create 2.2 listed in the different grades of electrostatic safe area. Table 2.3 is the safe area of the typical static data. 
An electrostatic establishment of the main areas of work include: 
(1) set up anti-static grounding system; 
Ground Resistance <10W (GJB12058-90: <= 100W); setting more ground-side; with General Electric to split, and so on. 
(2) the laying of anti-static floor mats and Taiwan; 
On the floor of the structure, materials, construction and inspection, maintenance and monitoring on a regular basis. Structure: 
1, overhead-type activities: for non-mobile load (equipment), less flow, communications cable and more occasions, not suitable for logistics frequent occasions; 
2, carpet: only the flow of people laid along (or plant area of 15% to 35%), not suitable for logistics load transmission; 
3, and laying plate (permanent-type): one-time laying of a comprehensive, easy adjustment process could be sent for loading logistics. 
Taiwan pad: double-compound rubber, the upper 105 ~ 108W, the lower 102 ~ 103W. And to the grounding resistance to security in the area; do not have the best metal pad and Taiwan, first, personal safety, and the other is to avoid things charger discharge. 
(3) to install devices to eliminate static electricity; 
If the entrance of the working areas, such as the conveyor belt. 
(4) staff in particular, the operator of static electricity protection: an anti-static with anti-static wrist strap, clothing, etc. 
(5) the correct operation of 
Take when using the device without touching the pin shell fuses, circuit boards installed when inserted last-sensitive device, plug the device is not charged and circuit boards, often touching the ground static column, not friction-type action, and so on; and prevent people and Direct delivery. 
(6) the use of anti-static devices: anti-static, such as containers, tools and so on; 
(7), anti-static control of the work area and the net degree of humidity. 

2, packaging, storage and transport of anti-static works measures 

The main purpose is to prevent static electricity generated: such as anti-static packaging, such as the potential pin devices, to avoid friction, such as the immediate grounding power dissipation. 
In the absence of safety zones or grounding system must be particularly careful! 
The role of anti-static packaging: 
1, to prevent static electricity generation and accumulation; (such as anti-static plastic tube shipment) 
2, so that the device short-circuit all of the pin, such as potential; (such as standard metal, conductive foam, the Class I electrostatic sensitive devices) 
3, external electric field shielding. 
The delivery process to avoid friction, contact, vibration and shock, and so on; to optimize the speed of transmission lines, power dissipation to take measures. 

3 electrostatic detection 


(1) used electrostatic detection instrument 
Electrostatic potentiometer, Zhaoou table (table high resistance), wrist strap detector, the monitor connected, and so on. 
Electrostatic potential total: conductor for the contact (to change the situation of conductive objects under test) and the insulator for the non-contact (use of the principle of electrostatic induction). 
Non-contact electrometer: a sense of style straight, rotating vane, vibration and capacitive-collector. 
(2) electrostatic detection classification 
At a time: regular, regular and temporary; 
According to the accuracy of the test at: quantitative and qualitative 
In accordance with sub-sites: on-site testing and laboratory tests, 
Table 2.4 is a major electricity company on the day-to-day monitoring of regulatory requirements; Table 2.5 is the qualitative test of static electricity; Table 2.6 is the on-site testing and laboratory testing. 

4, the management of static electricity protection 

(1) the establishment of integrity, strict control of anti-static process, to carry out the design, procurement, production technology, quality assurance, packaging, storage and transportation links and other sectors, Table 2.7 lists some of the aspects of the electricity used standard. 
(2) put up eye-catching signs of static sensitive devices, the map is a variety of anti-static 2.11 mark. In which (a) anti-static work area is a symbol, (b) and (c) is anti-static containers, aircraft components, such as vehicles and equipment on the mark; (d) is also dealing with anti-static objects and sites of the mark . 
(3) the training of static electricity protection. 
4.5 Summary 
(1) all the components sensitive to static electricity as a device; 
(2) In the absence of well-grounded, never to touch-sensitive devices or components; 
(3) If the IC technology is not anti-static line or work on the stage, they will be kept in the grounding of the shielding container; 
(4) with the IC board must deal with anti-static table; 
(5) wristband, every day quarantine programs should be tested to ensure that meet the requirements of parameters; 
(6) all instruments and equipment must be grounded; 
(7) IC flow of gases and liquids to keep low-speed; 
(8) in the absence of other anti-static measures, not to take anti-static tube installed in the IC;
(9) in the process of electrostatic potential use of fixed Ionic consumer appliances; 
(10) wristband to keep the human body and potential, and so on; 
(11) ESD protection device platform to maintain and potential, and so on; 
(12) can not be placed in the static random security in the region of insulating material. 
When the existence of electrostatic potential difference, static strength enough to puncture the surface of objects, or between isolation or direct contact with these objects, electrostatic discharge can occur. 
Therefore, to prevent any possible incident of electrostatic discharge only solution is to keep all objects such as a potential.
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