Function
of packaging, handling, and storage products is to limit possible impact of ESD
on the ESDS from:
1.
triboelectric
charge generation
2.
direct
discharge
3.
electrostatic
field
Materials
should have anti-static properties, be able to shield against direct
electrostatic discharges and electrostatic fields, and be conductive
(dissipative range).
1.
Receiving
/ inspection
-Are components properly packaged from vendor?
-Remove all non-ESD
packaging from area:
Standard bubble wraps,
packing peanuts, plastic bags, Styrofoam.
-Purchasing should insist that all ESDS items be
packaged in a shielded package.
-Repackage
if necessary
-Use of ESD labels / tape
ESD Markings alert handlers of contents. Important
if sending sensitive components through uncontrolled areas.
-Receiving station should be ESD safe
Products:
Bags: antistatic poly, shielding bags, bubble wrap, ESD
tape, mat / wrist strap or heel grounders.
2.
Storage
-Open parts bins, dissipative storage boxes
-Grounded shelving areas with conductive paint,
shelf liner,
-Items to use: bins / storage boxes
Precautions to take:
Shelving should be grounded and operators should be
grounded while stocking or picking items.
Products to use:
-Dissipative bins, storage boxes
-Shelving: shelf liner, conductive paint
-Heel grounders / ESD floor
3.
Transporting
Movement of carts and other wheeled equipment
through the facility can also generate static charges that can transfer to
products being transported
-Transporting ESDS from workstation to workstation
-Covered totes
-Racks / carts grounded to ESD floor. ESD safe cart
covers can keep dust off without generating charge.
-Personnel should be grounded
-Workstation should be ESD safe
Products to use:
ESD safe carts:
-Drag chains (don’t get as dirty as dissipative
wheels)
-Make sure all shelves are grounded.
-Covers
Tote boxes
Inplant handlers
4.
Production
Automated lines vs. manual line
-Any workstations on production line should be ESD
safe
-ESD safe areas should be well-marked (signage,
floor tape)
-Boards / components from storage to be removed from
shielding bags at ESD safe workstation using proper handling methods.
-Components/board can be stored on board rack or in-plant
handler as they move through production line
-Conveyor / rollers
-Dissipative
trays
-System
should be grounded
5.
Inspection
/ QC
Follow similar precautions as handling in production
6.
Packing
/ shipping
Different packing techniques for finished goods or
contract board items
-ESD safe workstation
-ESD safe packaging
ESDS boards /components should be packaged in shielding
bags or ESD safe component shippers
Additional precautions include ESD safe packing
peanuts, foam padding
ESD packing tape alerts recipients that items inside
need to be handles in ESD safe area
a.
Awareness
-Training / education
-Signage
b.
Top
down
-
participation
by all levels operators/supervisors/management
-
Must
have participation and buy in from all levels. Everyone must understand cost
savings and recognize ESD as QC issue.
-
documentation
of the reality of ESD
-
Ted
Danglemayer’s book ESD Program Management
-
Trade
publication articles documenting costs of ESD
c.
Developing
an ESD Control Program:
-EIA-625, Requirements for Handling
Electrostatic-Discharge-Sensitive Devices (ESDS)
-Appendix K of Mil Handbook 263B
ESD damage prevention checklist
-MIL-STD-1686C, ESD Control Program
Electrostatic discharge control program for
protection of electrostatic parts, assemblies and equipment.
-ESD Association Advisory, ESD ADV-2.0-1994
-Overview of ESD fundamental
guidelines from effective control of electrostatic caused problems.
-Discusses the causes of ESD
and the different types of device failure.
-Material electrical characteristics
-Device sensitivity: How much static protection is
needed
-Chapters on:
-Points of control
-Implementing an ESD control
program
-Audits and checklists
-Symbols
-Device testing
The
handbook also has sections that focus on specific areas of ESD Control.