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Why Most Static Programs Fail
A well designed, comprehensive, fully realized program
is a must for manufacturers serious about ESD control.
by David H. Long
Vice President, ESD Flooring, Inc.
Introduction
The year 1986 was very profitable for the static control industry. Electronics
companies, finally aware of the need for static-preventive wrist straps, bins,
bags, table mats and ionizers, spent more than 200 million dollars in the hopes
of eliminating electrostatic discharge (ESD). What did these firms get for their
money? Some organizations realized immediate improvements - both in yield and
in reduction of field returns. Others simply found an ESD program necessary
for successful solicitation and retention of contracts. Many are not sure just
what they got and worse, why they got it.
ESD has been recognized as a threat to electronic devices since the introduction
of blasting caps and detonators to the mining industry. Numerous technical articles,
awareness seminars and preventive products are readily accessible to industry.
The cause, effect and solution to the ESD is widely accepted and well documented.
Why, then, is it so difficult for engineers to convince management to provide
the funds essential for establishing an in-house static program? Many times,
ESD-control programs do not measure up to the anticipated objectives, or, even
more disheartening, are completely Ineffective. To a wide extent, these programs
never really had a fighting chance; they were doomed from inception.
A major manufacturer of computer peripherals was quite proud of its ESD program
and was not shy to point out its 300,000-dollar expenditure. However, an audit
became necessary when the new gate arrays used in a recently introduced product
were failing at an astounding rate. Also, field returns were eating away at
profits and at a hard-earned reputation. A thorough investigation of the situation
uncovered numerous broken links in a chain of protection dependent upon total
continuity.
The audit confirmed that the use of wrist straps, conductive containers, dissipative
table mats and ionizers were in compliance with the guidelines set by the manufacturer's
prospective customers. However, half of the wrist straps failed a simple continuity
test and many of those that did pass were either connected improperly or worn
too loosely to ground the wearer reliably. The table tops, installed by the
bench manufacturers, were grounded without the mandatory one-megohm resistor
in line. When questioned about ESD training, most assembly people commented
that they recalled viewing "some film about zaps and zings." The ionizers
blowers contained enough dust and dirt to allow only a whisper of the original
air flow to pass through them. The tote boxes, originally supplied with lids,
were being utilized uncovered because the lids were cumbersome and did not appear
to serve any purpose beyond that of dust collector.
The incident described is not an isolated circumstance. It is not uncommon
for manufacturers to feel that the success or failure of an ESD program is based
on the amount of money invested. What they often do not realize is that for
any ESD program to be successful, there are a number of factors that need to
be addressed prior to implementation. If obstacles are recognized in advance
and cannot be resolved, the project should not be undertaken. In most cases
though, the obstacles that lead to failure can be avoided, sometimes before
a single nickel is wasted.
The Eight Most Common Reasons Why ESD Programs Fail
- Little support from top management. Most engineers seek manager's
support before soliciting capital funding for a project. However, the appropriation
of funding should be the tip of the iceberg when it comes to management's role
in the development of a successful ESD program.
The most common reason for the failure of ESD programs is the lack of visible
support by top management. Management needs to show, by example, that everyone
- CEO and customers included - must exercise the precautions specified by the
static expert.
Furthermore, management should be prepared to show support by appearing at
training seminars and by giving a brief preliminary pep-talk relating the features
and benefits of the ESD program and the impact each individul will have upon
it.
Management should also praise departments with satisfactory records of ESD
prevention and provide assistance for those departments that fall short of
the mark. To be successful, ESD prevention requires teamwork - achieved through
consistency and dedication - between all levels of the organization.
- The Band-aid Approach as Opposed to a Permanent Solution. Many ESD
programs appear to have been based on the theory that there is never time to
do it right, but there is always time to do it over.
Many companies, faced with budgetary restraints, employ spot solutions rather
than take a long-range look at their options. Examples include the benefits
of conductive tile over dirty floor mats, Faraday6 cage boxes over disposable
shielding bags, or permanently installed benchmats over expandable soft table
pads. Also, grounds are often installed to the nearest electrical outlet with
easily disconnected snaps or low-gauge wire that will break after its first
encounter with a tote box.
Regardless of the extent of any static program, preventive measures should
be installed correctly the first time - when the cost is the lowest. It is
far less expensive to static-proof the environment (i.e., the floors, tables,
footwear and material-handling system) than it is to employ and police band-aids
that will soon require costly repairs or even replacement.
- Poor Training or No Training at All. Most companies are not prepared
to train the entire work force effectively in the dos and don'ts of static
control. A recent survey of 50 electronics companies found that most training
programs required attendees to watch a film about ESD in a crowded room followed
only by a brief explanation of the features and benefits of static control.
Many of the companies surveyed limite3d mandatory attendance at training seminars
to assembly-level personnel.
Effective static control is an all-or-nothing proposition. To thrive (and provide
a payback), the program must be a priority to every employee of a corporation.
The CEO can destroy a sensitive component with the same ease as the night janitor.
Many dollars are wasted on the purchase of high-quality ESD-prevention equipment
that sits in unopened boxes, or worse, is utilized improperly by uneducated
or ill-informed personnel. If in-house resources are not able to develop a
convincing and informative seminar, then it would be wise to seek outside assistance.
- No Follow-up After Program Implementation. Many ESD-Prevention items
require periodic functional testing, occasional maintenance and, often times,
replacement. Employees frequently require further educations and positive reinforcement
regarding their role in the ESD program. Wrist straps become ineffective from
build-up of insulative skin oils at the point of contact between the wearer's
wrist and the conductive fabric. Unless a continuous testing program is in
place, bad wrist straps could be in use for weeks or even months. Static bags
wear out and should be replaced. Dirty conductive tables and floors can become
insulative, defeating their purpose altogether.
The importance of proper maintenance and training reinforcement cannot be overemphasized.
The reliability of any ESD program depends upon constant monitoring and fine
tuning where necessary. ESD programs are most successful when one individual
is delegated management responsibility. His or her authority must be supported
by supervisors and recognized by fellow employees.
- Many Programs Are Implemented Only to Placate the Customer. Quality-conscious
organizations and corporations require all suppliers and subcontractors to
maintain a static-free environment. The fulfillment of this obligation is usually
confirmed by a visit from a vendor engineer. During this visit, the vendor
engineer searches for the presence of the static-preventive measures specified
by the particular contract. Noncompliance can result in withdrawal of the contract.
Short-sighted management teams sometimes implement an ESD program purely for
the purpose of satisfying a vendor audit. Often, the "solution" is
a program hastily installed and comprised of the least expensive materials
available. It is not uncommon for these organizations to slap an ESD program
together several times a year. Preventative maintenance, follow-up, and training
are virtually nonexistent.
At the insistence of those most interested in the elimination of costly throw-away
solutions (e.g., the accounting department), the problem is often eventually
corrected. A solid understanding of the problem, couple with the commitment
to purchase a long-term solution, is essential to the establishment of a dependable
and worthwhile ESD program. In the long run, a well-planned and properly implemented
ESD program easily pays for itself through improvements in quality, reliability
and reputation.
- Lack of Industry Standards. In view of the current lack of industry
standards, it is wise to test any proposed equipment, under in-house factory
conditions, regardless of the manufacturer's compliance with regulatory standards.
Before using specifications to compare products, it is imperative to obtain
a copy of the standard and determine the actual parameters of the test. It
is important to note that items that behave one way under controlled conditions
may perform differently in a factory environment.
- Inability to Locate a Deal with Reputable Suppliers. The price factor,
for many companies, still largely determines the selection of both product
and vendor. Little consideration is given to either the reliability of the
vender or to the range of services that he or she is prepared to supply. At
times, even the quality of materials is overlooked in the quest for low-budget
solutions.
Neglecting to investigate a vendor's credentials could lead to the downfall
of a well-intended, albeit cost-controlled program. Reliable vendors can be
easily identified by a brief examination of their products and by selective
screening of their customer base. Vendors should be prepared to speak knowledgeably
on all aspects of the ESD program, including training, maintenance and calibration.
- ESD control is limited to the manufacturing environment. Sensitive
electronic parts are most vulnerable to damage in the environment of the end
user - the customer. Once outside the manufacturing facility, the components
are subjected to static-charge environments. Ill-informed users within these
environments are unaware of the thousands of volts of potentially destructive
static that they carry on their clothing alone.
Despite the hazardous and potentially crippling conditions, the problem remains
unrecognized, oftentimes leading to redundant field service calls, excessive
downtime, and conceivably, loss of the customer.
Conclusions
The control of the ESD is a matter every electronics company must confront.
Maintaining the competitive edge in today's marketplace can hinge on an organization's
ability to deal successfully with the fundamental but elusive phenomenon first
recognized by the ancient Greeks over two thousand years ago. The problem, while
certainly not insurmountable, demands a formidable opponent in the form of a
well-organized, comprehensive, static protection program. The successful ESD
program depends upon careful planning by conscientious individuals, followed
by precise implementation, effective training, and thorough follow-up, originating
at the assembly line and progressing straight to the customer.
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