Establishing and implementing successful ESD protective packaging procedures requires a basic understanding of how sensitive devices may be damaged during or after packaging and how protective procedures work. Two basic events, charging (either triboelectric or contact with charged source) and discharging, ultimately can result in the destruction of microelectronic devices. In theory, these events could be avoided by preventing the motion inherent in the triboelectric charging process, by minimizing contact between or with insulators, and by keeping all surfaces at equal potentials. In practice, however, it is not possible to effect these safeguards. By its very nature, electronic manufacturing is a constant blur of motion. Devices must be moved from place to place and, in the process, they come into contact with a variety of materials. As a result, even highly visible controls, such as wrist straps, do not ensure that ESD-sensitive devices will be protected from damage. In the absence of air ionization and for Class 0 (less than 200 V), static-control materials and deployment of special ESD controls are essential.
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