Implementing a successful ESD programme - a case study

Dr Jeremy Smallwood, Electrostatic Solutions Ltd. 

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.

One automotive company's experience

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.

A two step approach was taken - firstly to harden the components and systems, and secondly to implement a new ESD programme.

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.

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.

An eight point plan was developed from these rules;

1. Documentation - procedures on handling, specifications for processes, service, packaging, suppliers

2. Standardisation - of ESD control products and materials, and labelling

3. Training - awareness training for production, engineering, maintenance, purchasing, service and suppliers

4. Central information source - disseminating information

5. Research and development - on ESD control applications and test methods, and updating knowledge

6. Audits - daily audits of wrist and heel straps, and regular audits of other items, procedures and suppliers

7. Monitoring failure rates - to determine effectiveness of measures

8. 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.

The second step of implementation was the installation of facilities.

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.

As a result of the programme, failure rates dropped by nearly 50%. Other benefits were realised.

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.

Various key factors were felt to have led to success

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.

Perhaps a key conclusion lies in observing the importance of assessing and monitoring ESD failures and associated costs. 

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.

References

Lai E. C. Y., Plaster J. S. ESD Control in the automotive electronics industry - a case study. Proc EOS/ESD Symposium 1987 pp10-18