ESD requirements for an organization can be established by referring to ANSI/ESD S20.20 standard. This ANSI/ESD S20.20 standard is applicable to all electronics industry such as Semiconductor Wafer processing fab, Semiconductor Assembly and Test, Printed Circuit Board (PCB) assembly, Disk drive, Flat Panel Display and any other industry which involve in producing or assembling ESD sensitive parts.
As the ESD Control program is established with the intention to protect the ESD sensitive parts from being damaged by Electrostatic discharge (ESD), therefore the most sensitive level of the ESD sensitive parts being handled in the plant must be addressed upfront in the ESD Control program plan.
The ESD sensitivity level of most electronic components can be known by inquiring the information from the Design department or from the Material Data Sheet of the part.
When this information is not available, the organization can set up his ESD control as per the ANSI/ESD S20.20 standard scope requirement to protect ESD sensitive part with ESD sensitivity level equal to or greater than 100 volts HBM.
More stringent ESD requirements are needed for protecting the more sensitive ESD parts.
Besides addressing the protection capability of the ESD Control program, the ESD Control program plan shall also address both the Administrative and Technical requirements that support its provision and protection capability for the most ESD sensitive part that the organization can safely handle.
The ESD Control program administrative requirements include:
• Training
• Compliance Verification
Training plan: Under the Training plan, the organization shall include both its initial and recurrent ESD awareness and prevention training program to all his employee who handle or otherwise come into contact with the ESD sensitive parts. Methodology of ESD training provision shall be defined along with the training frequency.
The organization also needs to define the method used to verify the comprehension of the trainee on the subject being trained and its training adequacy and the method of maintaining the training records.
Compliance verification: Under the Compliance verification plan, the organization is basically verifying the ESD compliance of the controls being set up in the ESD Control program plan. That includes verifying the Technical requirements compliance and other ESD control compliance. The former verification involves measurement monitoring and the latter usually is a non-measurement monitoring process.
The compliance verification activity shall be established and documented, including the technical elements to be verified, the verifying frequency and the measurement control limits, the methods and equipments used during the verification process.
The ESD compliance records shall then be maintained as evidence of conformity to the controls of the ESD control program plan.
The ESD Control program plan technical requirements basically include:
• Grounding/ Equipotential bonding system
• Personnel grounding
• ESD Protected area requirements
• Packaging systems
• Marking
• Equipment
• Handling
Verifying the Technical elements shall be done based on method spelled out in the standards referenced in the ANSI/ESD S20.20 standard.
Tailoring statement must be documented in the ESD control program plan when the method used by the organization differs from those in the standards.
The ESD Control program plan needs to be reviewed periodically to ensure the ESD sensitive parts being handled in the plant is safely protected from esd damage.
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