iNEMI Task Force Addresses RoHS Transition Issues
 
High-reliability community wants to ensure availability of 
components that meet their needs
 
HERNDON, VA (August 25, 2005) — The International Electronics Manufacturing 
Initiative (iNEMI) today announced publication of recommendations for 
safeguarding the dependability of high-reliability products as the supply chain 
converts to lead-free components and materials.  The consortium’s High-Reliability 
RoHS Task Force is calling for continued availability of tin-lead 
(SnPb)-compatible components for exempted products, and for a standardized strategy of 
mitigation practices and testing methods to minimize the risk of tin whiskers.
“The iNEMI High-Reliability (Hi-Rel) Task Force consists of OEMs and EMS 
providers whose products are characterized by long service life and 
high-reliability requirements,” says Jim McElroy, CEO of iNEMI.  “Maintaining high product 
reliability is absolutely critical to these companies’ survival.  They are 
very concerned about the transition to lead-free and have banded together to 
provide a unified voice and message to the supply chain.  We are currently 
surveying the components supply base to see if it makes sense to organize an industry 
forum that will bring together high reliability users and suppliers to 
further discuss these needs.”
Continued Availability of Components
Certain products are exempt or out of scope under the European Union’s RoHS 
Directive and will be allowed continued use of lead in solder for reliability 
purposes.  These products include servers, storage and storage array systems, 
monitoring and control instruments, plus network infrastructure equipment for 
switching, signaling and transmission as well as network management for 
telecommunication.  However, the supply chain, which is increasingly driven by 
high-volume, low-cost applications that do not have stringent reliability 
requirements, is converting (or has converted) to lead-free.  Many suppliers plan to no 
longer offer SnPb products.
Several compatibility issues have been identified as high-reliability OEMs 
and EMS providers try to "mix and match" Pb-free components in exempted SnPb 
assembly processes. 
“The RoHS Directive provides ‘lead in solder’ exemptions for important ‘
mission-critical’ and high-reliability systems, ostensibly because the Commission 
recognized that industry does not yet have adequate field data or verified 
acceleration models to ensure the reliable functioning of these critical 
products if lead-free solders were used.  Their intention was to guard against 
unnecessary risk in applications where failure could be anything from problematic to 
catastrophic,” says Joe Smetana, principal engineer, advanced technology for 
Alcatel and chair of the iNEMI Tin Whisker User Group.  “Companies that 
manufacture high-reliability, long-service-life systems must be assured of the 
availability of components that are compatible with tin-lead 
(more)
iNEMI Task Force Addresses RoHS Transition Issue/page 2
assembly, not only to provide continued quality and performance in new 
products but to maintain products already in use. Many telecom, server, monitoring 
and control instruments, or storage products, for example, often have a field 
life of 10 to 25 years and are high-end systems that customers will want to 
repair rather than replace.” 
Mike Davisson, distributed materials engineering manager for Agilent 
Technologies, points out that ball grid array (BGA) components are of particular 
concern.  He notes that solder balls are designed to operate within a particular 
set of process and materials parameters.  
“Lead-free BGAs are designed to be assembled with tin-silver-copper solder 
paste, not tin-lead solder paste.  We need a continued supply of tin-lead ball 
BGAs.  We cannot take lead-free BGAs and attach them to boards using tin-lead 
solder with today’s typical assembly process.  Industry experience has shown 
that doing so can produce lower assembly yields and less reliable interconnects,”
 Davisson says. 
Tin Whisker Mitigation
The other area of concern is tin whiskers. The predominant whisker mitigation 
strategy for more than 50 years has been the addition of Pb to the tin 
plating.  As Pb is eliminated from electronic products, many component suppliers are 
proposing the use of pure tin plating as the most convenient and least costly 
strategy for meeting RoHS requirements.  However, especially for the 
high-reliability user community, the pure tin strategy presents reliability risks due 
to the whisker-forming tendencies of pure tin and tin alloy plating.  
Economic realities are driving most component suppliers to offer tin and/or 
high tin content (>95%) Pb-free finishes, and the availability of multiple 
surface finishes will not be a long-term option in most cases.  The High-Rel RoHS 
Task Force has defined a set of requirements to ensure that their suppliers 
provide the least whisker-prone finishes possible. These companies (listed 
below) are requiring their suppliers to combine mitigation practices with testing.
“We are requiring that our suppliers employ a proven whisker mitigation 
strategy, such as nickel underlay or annealing,” says George Galyon, senior 
technical staff member, IBM, and chair of the iNEMI Tin Whisker Modeling Project. “
However, since mitigation techniques can vary significantly in effectiveness, we 
are also asking for supporting measurements — meaning testing — to provide 
objective evidence of mitigation efficacy.”  
The iNEMI Hi-Rel Task Force companies will require electronic component 
suppliers to implement the following recommendations for high-reliability 
applications: 
1.       Adopt one of the iNEMI-recognized whisker mitigation practices as an 
integral part of Sn and/or high Sn content (>95%) Pb-free plating processes, 
as outlined in the iNEMI Tin Whisker User Group’s Recommendations on Lead-Free 
Finishes for Components Used in High-Reliability Products, Version 3 (updated 
May 2005). This document can be downloaded from:
http://thor.inemi.org/webdownload/projects/ese/tin_whiskers/User_Group_mitigat
ion_May05.pdf 
(more)
iNEMI Task Force Addresses RoHS Transition Issue/page 3
2.       Perform testing and adhere to the qualification criteria of either 
the iNEMI Tin Whisker Acceptance Test Requirements (July 28, 2004) or the final 
agreement of the JEDEC JESD-201A qualification criteria (Environmental 
Acceptance Requirements for Tin Whisker Susceptibility of Tin and Tin Alloy Surface 
Finishes, currently in industry review), in conjunction with the JESD22-A-121 
test method (Test Method for Measuring Whisker Growth on Tin and Tin Alloy 
Surface Finishes). The iNEMI test requirements document can be downloaded from:
http://thor.inemi.org/webdownload/projects/ese/tin_whiskers/Tin_Whisker_Accept
_paper.pdf
JEDEC standards are available at www.jedec.org or 
http://www.jedec.org/download/.
3.       Continue to provide an alternative non-whiskering finish, such as 
SnPb or nickel-palladium-gold (NiPdAu), until the requirements of the 
iNEMI/JEDEC acceptance tests have been met.
The following companies from the iNEMI High-Rel RoHS Task Force support the 
concepts as stated above:  


Agilent Technologies, Inc.
Alcatel
Andrew Corporation 
Cisco Systems, Inc.
Celestica, Inc.
Delphi Electronics & Safety
Hewlett Packard Company
IBM Corporation
Intel Corporation
Jabil Circuit, Inc.
Lucent Technologies
Plexus Corp.
Sanmina-SCI Corporation
Solectron Corporation
Sun Microsystems, Inc.


 
The group’s recommendations are available from:
http://www.inemi.org/cms/projects/ese/High_Rel_RoHS.html 
About iNEMI
The International Electronics Manufacturing Initiative’s mission is to assure 
leadership of the global electronics manufacturing supply chain.  Based in 
Herndon, Va., the industry-led consortium is made up of approximately 70 
manufacturers, suppliers, industry associations and consortia, government agencies 
and universities.  iNEMI roadmaps the needs of the electronics industry, 
identifies gaps in the technology infrastructure, establishes implementation projects 
to eliminate these gaps (both business and technical), and stimulates 
standards activities to speed the introduction of new technologies.  The consortium 
also works with government, universities and other funding agencies to set 
priorities for future industry needs and R&D initiatives.  For additional 
information about iNEMI, visit www.inemi.org.
###

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