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NEMI and ITRI Collaborate to Investigate Issues Relating to Effects of
Lead-Free Solder on the Manufacture of PWBs
Projects Focus on Surface Finishes and Laminates Suitable for Processing at Higher Temperatures
Press and Project Contacts at bottom of page
HERNDON, VA and AUSTIN, TX—April 3, 2000—The National Electronics Manufacturing Initiative (NEMI) and Interconnection Technology Research Institute (ITRI) today announced their collaboration on efforts to evaluate surface finishes and laminate materials for printed wiring boards (PWBs) used in lead-free electronics assemblies. ITRI will do extensive assessment of test vehicles to determine the finishes and laminates most compatible with lead-free solder and make this data available to the Components Sub-group of NEMI’s Lead-Free Assembly Project.
Earlier this year, NEMI recommended that the industry standardize on the use of Sn3.9Ag0.6Cu as a replacement for tin-lead solder in reflow applications (see press release — January 24, 2000). Use of this alloy will raise the melting point by as much as forty degrees, which will impact a number of the materials and steps in the assembly process.
"As part of its activities, the NEMI Lead-Free Assembly Project intends to demonstrate production-ready parts, materials and processes for lead-free printed wiring board (PWB) assemblies and to cooperate with component, board and equipment manufacturers to allow for the smooth transition to lead-free manufacturing processes," said Jim McElroy, executive director and CEO of NEMI. "This collaboration with ITRI is essential to achieving these objectives. They are providing valuable foundation work that will help complete the picture of the lead-free electronics infrastructure."
Surface Finish
Finishes are used on PWBs to protect the boards and make them solderable. Today, tin-lead is the most commonly used finish, but there are a number of lead-free alternative finishes already in use. However, there is little or no information about how these alternatives will work with NEMI’s lead-free solder choice, which requires higher processing temperatures. ITRI established a Lead Free PWB Surface Finish Project to address this need. The project is designing and building test vehicles to evaluate the compatibility, reliability and manufacturability of lead-free PWB finishes when used with lead-free solders. The effort is headed by Wayne Johnson of Auburn University and sponsored by the PWB Manufacturing Technology Center (PMTEC). Test vehicles will be evaluated for wetability using several different no-lead solders, including the one recommended by NEMI, and a tin-lead solder control. Data from these tests will be provided to NEMI and ITRI members to guide selection of PWB finishes for assembled board reliability studies.
Laminate Materials
Another key concern with lead-free solders is whether the PWB itself can survive the higher processing temperatures without degrading reliability, electrical properties, etc. ITRI is building board structures using various laminate materials provided by the leading laminate material suppliers, and putting these boards through a series of tests (with the results provided to NEMI and ITRI members). In addition, ITRI members will provide NEMI with appropriate test boards for NEMI’s assembly reliability testing.
"This collaboration between our two organizations is a good example of the way that technology deployment is being done as OEMs increasingly divest themselves of manufacturing capabilities and rely more heavily on EMS and supplier companies," said Marshall Andrews, CEO for ITRI. "The OEMs have provided requirements and timeframes through NEMI, and the ITRI manufacturers and suppliers pick up the gauntlet and take specific steps to meet those requirements. This is exactly why NEMI and ITRI were formed."
In addition to evaluating cost-effective lead-free component/PWB terminations and assessing reliability, NEMI’s Components Sub-group and ITRI’s project teams will work with JEDEC, IPC and other related standards bodies. Their objective is to adapt standards to reflect new materials and processing parameters associated with use of lead-free solder and high-temperature rated components/PWBs.
About NEMI’s Lead-Free Assembly Project
The NEMI Lead-Free Assembly Project was formed in 1999 to help North American companies develop the capability to produce lead-free products by 2001, with an eye toward total lead elimination by 2004. The project is chaired by Edwin Bradley of Motorola and co-chaired by Richard Charbonneau of StorageTek. Project work is organized into four sub-groups: (1) the Alloy Selection Sub-group, headed by Carol Handwerker of NIST; (2) the Solder Reliability Sub-group, chaired by Gordon Whitten of Delphi Delco with John Sohn of Lucent serving as co-chair; (3) the Components Sub-group, directed by Rich Parker of Delphi Delco; (4) the Process Development Sub-group, headed by Jasbir Bath of Solectron; and (5) the Environmental Monitoring Sub-group, chaired by Ron Gedney of NEMI.
About ITRI
ITRI is an industry-led consortium sponsored by IPC for collaboration among the electronic interconnection industry, government and academia. Its purpose is to enhance the global competitiveness of the North American electronics interconnection industry by enabling collaboration among its members to accelerate development and application of revolutionary and evolutionary technology. ITRI has over 60 member companies currently working on 19 different technology development and deployment projects.
The IPC is a US-based trade association dedicated to the competitive excellence and financial success of its nearly 2,500 member companies which represent all facets of the electronic interconnection industry, including design, printed wiring board manufacturing and electronics assembly. As a member-driven organization and leading source for industry standards, training, market research and public policy advocacy, IPC supports programs to meet the needs of a $26 billion US industry that employs more than 250,000 people.
Interconnection Technology Research Institute (ITRI)
11801 Stonehollow, Suite 400
Austin, Texas 78758-3263
Tel: 512-833-9930
Fax: 512-833-9925
www.itri.org
About NEMI
The National Electronics Manufacturing Initiative was formed in November 1994 to facilitate long-term North American leadership in electronics. The industry-led consortium is made up of over 50 electronics equipment manufacturers, suppliers, associations, government agencies and universities. NEMI’s members represent a combined total of more than $200 billion in 1998 revenues and employ more than 1.25 million people.
NEMI roadmaps the needs of the North American electronics industry, identifies gaps in the technology infrastructure, establishes implementation projects to eliminate these gaps, 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 further information, contact:
Cynthia Williams
207-871-1260
cwilliams@nemi.org
Diana Hempstead
ITRI
512-833-9930
dhempstead@itri.org