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Implementing a successful ESD programme - a case study
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| Dr Jeremy Smallwood,
Electrostatic Solutions Ltd.
Please email
me your comments on this article!
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To be successful an ESD control programme has to
sell itself to all levels of management and to employees, as being
consistent with their objectives and the dynamics of the company.
Demonstrating ESD failures and costs is an
important factor in achieving senior management support for
investment. Management commitment must be in the form of adequate
manpower and funding. The ESD programme must be implemented as a
package - the programme is only as good as its weakest link.
Providing information and promoting awareness
amongst personnel is vital - aware and motivated shop floor
personnel are the first line of defence against ESD damage. For most
companies, confidence in ESD control measures is gained through
training and hands on experience, published articles, and
benchmarking against other company practices. |
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One automotive company's experience
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In the 1980's, Delco Electronics Corporation performed a series of
in-house studies and as a result, commenced developing and
implementing a new ESD control programme. At the 1987 EOS/ESD
Symposium Lai and Plaster published a summary of their experiences.
Engineers today working to implement or upgrade their ESD facilities
will recognise the challenges they faced and find their observations
valuable.
The facilities under study were high volume electronics
manufacture and design, ranging from wafer fabrication to final
assembly. It covered 5 sites and 8 plants at the main site,
employing over 18000 people, and including surface mount
technologies, automated handling and manual operations. According to
the authors, the concepts of the ESD control system used were
applicable to large and small companies.
One study compared and older product A and newer product B. The
latter had a larger number of sensitive components but the
manufacturing system included state-of-the-art ESD control
philosophies. Whilst the percentage failure rate on product B
remained low, the failure rate on product A had risen from 9% to 17%
over the two year study period. A second study estimated that EOS/ESD
cost the company $22m over a 2 year period. Further studies showed
that the number of sensitive devices used had risen by 500% since
1980 and existing handling and packaging methods were no longer
adequate. These studies prompted the development of a corporate ESD
control system.
The existing system was inconsistent and lacked proper
maintenance, and awareness. A mixture of control techniques were
used, and static dissipative and shielding packaging were often
inappropriately applied. ESD control product specification was often
left to purchasing personnel, based on price, delivery, and
published specifications. |
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A two step approach was taken - firstly to harden the components
and systems, and secondly to implement a new ESD programme.
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The first step was to harden components and systems against ESD, by;
- Increasing awareness and expertise of design engineers through seminars and literature
- Monitoring of failures, by communicating and working between the disciplines
- Joint research with other companies and universities.
The second step was development of a new ESD control programme.
Three simple rules formed the basis of this;
- Sensitive parts must be handled at an ESD protected
workstation
- They must be transported in conductive containers or shielding
bags.
- Grounding of personnel is essential. Where it is not practical for operators to wear wrist straps, conductive flooring and footwear grounding must be used.
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An eight point ESD plan was developed - the next step was to
sell this to the management. The commitment must come in the form of manpower and funding.
The system represents
a change in company culture - a new way of life.
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An eight point plan was developed from these rules;
- Documentation - procedures on handling, specifications for
processes, service, packaging, suppliers
- Standardisation - of ESD control products and materials, and
labelling
- Training - awareness training for production, engineering,
maintenance, purchasing, service and suppliers
- Central information source - disseminating information
- Research and development - on ESD control applications and
test methods, and updating knowledge
- Audits - daily audits of wrist and heel straps, and regular
audits of other items, procedures and suppliers
- Monitoring failure rates - to determine effectiveness of
measures
- Monitoring of ESD prevention costs - investment, operating
costs, as well as personnel costs
The first step of implementation was to sell the system to all
levels of management as a package. Half implementing ESD measures is
a waste of time and resources - the programme is only as good as its
weakest link. The control programme was proposed as a vital step in
achieving World Class Quality, in tune with the Total Quality System
and statistical programme controls being implemented at the time.
Earlier studies had given them the facts to back up their proposals.
Lai & Plaster comment;
"The response from the upper management was
overwhelming. As soon as they could see what EOS/ESD damages
meant for the company and that there was an organised,
comprehensive and cost effective approach to control the
damages, approval was granted with a request to reduce the
implementation phase from the planned 18 months to 12 months so
as to reap the benefits as early as possible. Because the upper
management readily stepped up to the situation and took action,
the ripple effect that followed through the organisation greatly
reduced the resistance to change and generated grassroots
co-operation and commitment during the whole implementation
process."
The commitment must come in the form of manpower and funding. The
system must not have a start and end date - rather it represents a
change in company culture - a new way of life. |
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The second step of implementation was the installation of
facilities.
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The second step of implementation was installation of facilities. A
survey of existing facilities provided a baseline, with the
objective of identifying what additional ESD protection was
required. Surveys involved manufacturing, production control,
manufacturing engineering, maintenance, and quality assurance
representatives. In the process, product flow was reviewed from a
material handling view, as well as the design of optimal system for
human factors, methods and ESD control. Materials and labour costs
were then estimated. The materials could then be ordered,
capitalising on quantity discounts and customised items for optimal
materials handling. |
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As a result of the programme, failure rates dropped by nearly
50%. Other benefits were realised.
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As a result of the programme, product A failure rates dropped by
nearly 50%. Failures for one MOS device dropped from 9400ppm to near
zero. As an unexpected benefit, a drastic drop in machine downtime
was also reported in areas where ESD control had been implemented.
One department alone reported savings of $26k per annum in downtime.
Other benefits were realised. By testing and evaluating ESD
control products, the most cost effective and reliable products were
consistently purchased throughout the company with significant
savings. As a side benefit, implementation of more effective
materials handling led to savings of labour and inventory costs.
Once the programme and facilities were in place, there was a need
to make ESD control part of the culture and way of life. This
underlined;
- The need for a central information source that championed ESD
with information and communication.
- Continuous research and development to keep at the leading
edge of ESD technologies, with identification of weak spots and
upgrading of the ESD control system.
- Monitoring of failures and costs to measure the effectiveness
of the system, to close the loop of ESD control.
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Various key factors were felt to have led to success
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Various key factors were felt to have led to success. These
included;
- An environment of organisational change driven by foreign
competition, with an increased emphasis on quality and customer
satisfaction.
- A knowledgeable and committed champion who identifies with the
objectives of the company and sees the undertaking as a vital
step towards those objectives;
- A systematic approach involving sufficient checks and balances
whilst remaining flexible enough to respond to change
- Management commitment, recognising the need to change and
improve ESD control. The presentation of an ESD impact
assessment is effective in focusing attention on the
opportunities. However, implementation would be difficult
without support from all levels.
- Project management- co-ordinating a plan of action in
consultation with those involved, and drafting a schedule for
completion
- Training and publicity - raising awareness of ESD, what it is
doing to the company, and what can be done to improve the
situation.
- Grass root support - Properly trained employees make a
significant contribution to the implementation and maintenance
of an ESD control system. The feeling of participation generates
strong support.
- Co-ordinators are vital to the successful implementation of
the detail of the programme and acting as an information source,
and keeping abreast of developments. They should not be
distracted by other responsibilities.
- Benchmarking - awareness of practice in other companies, and
sharing information and experiences.
- Futuring - adjusting the system, and the roles of personnel,
to change.
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Perhaps a key conclusion lies in observing the importance of
assessing and monitoring ESD failures and associated costs.
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Many of the lessons learned in Delco's experience are as relevant
today as they were in the mid 1980's. Today's engineers implementing
and updating successful ESD programmes in the face of changing
technologies and increased component sensitivities, may find the
challenges remain largely the same.
Perhaps a key conclusion lies in observing the importance of
assessing and monitoring ESD failures and associated costs. Without
this step, the control programme has no feedback for evaluation and
optimisation, and management have no information on which to base
sound ESD investment decisions. In this situation, the likelihood of
achieving the vital support required at all levels, and successful
ESD programme implementation, must be severely diminished. |
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References
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Lai E. C. Y., Plaster J. S. ESD Control in the automotive electronics industry - a case study. Proc EOS/ESD Symposium 1987
pp10-18
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