Electronic Design

Lead-Free Means You're Still In The Game

The European Union’s RoHS deadline has come and gone, though some companies are still scrambling to comply.

Did your company make it? We're about a week past the July 1, 2006 deadline for compliance with the European Union's Restrictions on Hazardous Substances (RoHS) directive. Yet some companies still are working to ensure their products are lead-free. Getting the lead out under the EU's demanding new environmental rules hasn't been easy, especially for OEMs, who have ultimate responsibility for RoHS compliance.

"This is a big challenge for them because they're concerned about the usability and the serviceability of the components they're about to receive," says David Haataja, vice president and general manager of Underwriters Laboratories' Restricted Substances Compliance Solutions. "Many are still in the planning stage. That's tough because the deadline is coming up fast and putting a product on the market is your declaration of conformance. So, there's still some scrambling going on."

Clearly demonstrating due diligence is critical, says Haataja. At a minimum, this means keeping careful data records, monitoring and auditing suppliers, responding to customers' questionnaires and surveys, and obtaining Certificates of Certification. Haataja also suggests making product testing data available to customers.

In Hewlett-Packard's case, what's new is old in environ-mental terms. HP began investigating alternative soldering techniques in the early 1990s, essentially as part of developing a broader environmental perspective. "We were trying to understand the implications of eliminating lead from our products," says John Frey, HP's manager of Corporate Environmental Strategies.

But many companies are only now getting with the program. To help its 2300 member companies in the interconnection sector of the industry, IPC-Association Connecting Electronics Industries has launched its Certification for RoHS Lead Free Electronics Assembly Process Capability Program in North America and Europe.

"The IPC certification audit program has a long name but a simple goal, and that is to audit an electronics assembly facility—whether it's an OEM or EMS \[electronic manufacturing service\] company—to determine if the company's facility is capable of producing product to meet the lead-free requirements of the RoHS directive," says John Kania, IPC director of assembly industry programs. "The audit is not designed to, and cannot ensure, a facility will produce RoHS lead-free compliant products."

Kania says the certification audit program is a rigorous series of steps culminating in a two-day audit of the site's assembly operations. "The program allows both large or small companies to benchmark their processes and to judge their capabilities to meet RoHS lead-free assembly requirements," he says.

The program consists of 15 technical categories covering assembly-related issues such as equipment capability and compatibility, employee training, material compatibility, component handling, materials declaration, and documentation procedures. The audit itself will consist of more than 300 questions along with an on-site review by an IPC-trained auditor. By passing both the written and on-site audits, companies will confirm their lead-free process capability.

"Companies will not receive a rubber stamp certification," notes Kania. "This is an in-depth program that requires an exhaustive and thorough audit of one's processes."

The certification audit program took seven months to develop. So far, two EMS facilities in the U.S. have been certified following beta testing of the program. Solectron's facility in Charlotte, N.C., was the first beta test and the first Tier 1 EMS facility to receive certification. Raven Industries of Sioux Falls, S.D., successfully completed the second beta test on May 1.

OEMs and industry suppliers then evaluated and approved the structure and content of the program. Additional information on lead-free certification is available by downloading the program brochure and a sample audit checklist at www.ipc.org/LFCert.

WE'LL BE BACK
Like many large OEMs, HP has been auditing its vendors for years. "Start with the fact that HP is a very big customer with lots of vendors. That in itself generates a certain level of interest," says Frey.

"But you get a different level of interest when you say to a vendor that you're going to visit their operation and see how they're doing against our set of criteria," he adds. "And when you tell them you're going to be back next year, or if we find issues and say we'll be back in six months to see what kind of progress they're making in areas of concern—especially if it's something that might jeopardize our relationship—you get a whole different level of interest." Frey also says that HP usually is willing to work with its vendors to correct technical or other issues.

"Even companies that have explored lead-free know that research isn't enough," says John Perry, IPC technical project manager and conference director.

UL also has developed two new programs designed for organizations seeking to demonstrate due diligence in compliance with RoHS. Under the RoHS Product Certification Program, UL tests representative samples of a product at the homogeneous level for all six substances restricted by RoHS.

UL's Restricted Substances Management Systems Registration assesses an organization's compliance with the standards established by the International Electrotechnical Commission Quality Assessment System for Electronic Components (IECQ QC 080000 HSPM), which deal mainly with process management issues and generally require that organizations have implemented processes to identify and control the hazardous substance content in their products.

"UL created these services in response to the need in the industry for additional confidence when self-declaring their products are in compliance with the RoHS directive," says Haataja.

By most accounts, the industry still has plenty of work to do at the design level. Jasbir Bath, a manufacturing engineer with Solectron, says industry companies are still trying to understand how lead-free processes impact their product designs.

"Many companies are asking how design standards will change to address lead-free soldering relative to tin-lead soldering," Bath says. But he doesn't believe design standards are changing, at least not from current production information for lead-free consumer products, including cell phones and laptops. He also says Solectron is documenting these and related issues in a design guide.

THE ALTERNATIVES
Most RoHS-compliant pc-board manufacturers admit they were still working and reworking their board designs and materials formulations prior to July 1 and probably will continue to do so for some time.

Jeff Schafer, senior vice president-product at components and test equipment distributor Newark InOne, says the availability of a wide range of new alloys with a variety of surface compatibilities, finishes, and process temperatures is causing a lot of market confusion. Larry McQuinn, vice president of sales and marketing of pc-board maker Advanced Circuits, also sees confusion from customers who think that as long as the finish on the board is lead-free, they’re in compliance. “They haven’t given enough thought to the assembly of the board,” he says.

Bath suggests board designers label their design drawings with the “e” code designation to indicate the type of lead-free solder to be used on the board. “This helps identify the correct lead-free solder to use for assembly, rework, and field return repair operations,” he says. (Details on code designations are available in the JEDEC DESD-97 and IPC 1066 standards.)

Further complicating the transition to lead-free components, McQuinn says, is that some assembly processes require high cycling temperatures that may call for different types of laminates than designers have been used to. “So, there’s still some confusion in the industry about temperatures in producing lead-free pc boards,” he says. The problem in replacing the lead in solder alloys with other elements is that lead-free alloys melt at a higher temperature than traditional tin/lead alloys. A 60/40 tin lead mixture melts at around 180°C (356°F), compared with 227°C (441°F) for lead-free.

The defense and aerospace industry sectors, which are exempt from the lead-free restrictions under RoHS, ironically may have the toughest time adjusting to the new legislation. Both industries want to avoid lead-free products because they believe they’re susceptible to tin whiskers growth, which could eventually hinder the performance of their products or systems.

With most chip suppliers switching over to lead-free devices, it may be increasingly difficult for the defense and aerospace industries to obtain leaded parts. Still, some chip and pc-board manufacturers will continue to run leaded lines for exempt applications, at least until demand begins to wane.

Two organizations, JEDEC and IPC, have released two documents to help manufacturers reduce the risk of tin whiskers in lead-free devices. JEDEC standard JESD201 and JP002, a joint publication of JEDEC/IPC, were developed specifically to help address mitigation practices, process controls, and verification testing in lead-free devices. Both documents can be downloaded from JEDEC’s Web site.

Also, the United Kingdom’s National Physical Laboratory (NPL) has published nine separate reports based on research sponsored by the European Lead-Free Soldering Network that deal with lead-free soldering in electronic components. The reports can be downloaded for free from the NPL Web site at www.npl.co.uk/ei/publications.

TI GETS A RUNNING START
Texas Instruments got an unexpected jump on much of the industry when it started producing lead-free nickel-palladium-gold components in 2000, mainly because they were similar in structure to the parts TI was already making. TI found that adding gold to the process gave the material some advantages.

“Having a whisker-free solution is a tremendous advantage right now,” says Doug Romm, a senior member of the technical staff of TI’s Standard Linear and Logic Product Group. “This has really paid off for us because most of our competition is using tin finishes.” Nickel-palladium-gold is also backward-compatible with exempt applications, like military/aerospace, some medical devices, and certain telecom applications. (While backward compatibility might seem to be an obvious goal as manufacturers begin releasing compliant parts, Schafer of Newark InOne believes that 5% to 10% of them have produced RoHS-complaint parts that do not perform exactly the same as leaded, or noncompliant, versions.)

If it’s inherently lead- and whisker-free, why doesn’t everyone go with nickel-palladium-gold? For one thing, says Ken Farrington, TI’s RoHS office manager, it’s an expensive transition. Also, he says, “We think a lot of our competitors weren’t willing to take that gamble with the RoHS deadline so close, so they had to go to matte tin. For them, it was mainly a logistics issue.”

But he says some TI competitors are making moves suggesting an eventual shift to nickel-palladium-gold. “You see that in some product portfolios,” he says. “We expect to see a slow migration to nickel-palladium-gold over the next several years.”

At this point, 98% of the lead-frame components Texas Instruments is shipping are nickel-palladium-gold. The remaining 2% are matte tin, but Romm says these components eventually will be switched over to nickel-palladium-gold. The holdouts are some subcontracted parts. Romm says that some of TI’s subcontractors are already producing nickel-palladium-gold components.

FORECASTING
RoHS compliance also has made forecasting and inventory control much more complicated. “Forecasting is difficult,” says Cindy Newell, senior manager of tactical marketing at Actel Corp., which supplies programmable logic products such as field-programmable gate arrays (FPGAs).

“Some of our customers have switched to lead-free devices without warning, or at different times. We have to have products in place to handle their demands. If we don’t, the lead times can be long, up to 10 to 13 weeks,” Newell says, adding that some of Actel’s assembly vendors have been working at 100% capacity. “So, you now have an unforecasted demand and their lead time pushes out.”

Then there’s the enforcement issue, which continues to baffle even the most knowledgeable RoHS sources in the industry. Despite murmurs of the publication of an EU RoHS Enforcement Guidance document, no one seems to know how the EU and its member states plan to enforce RoHS compliance.

“It’s not clear,” says Newell. “That’s why we’re seeing so many questionnaires, with questions ranging from, simply, ‘Are you compliant, yes or no,’ to very lengthy and complicated product surveys.”

HP’s Frey agrees. “It’s not very clear,” he says. “We know what we’ve been told, and we’ve made a fair number of guesses. But until the directive actually kicks in, and you start seeing the member countries doing their thing, it’s going to be very tough to tell what’s going to happen.”

Frey says it probably will vary from one EU country to another. “It’s going to be very challenging. Right now, everyone is making assumptions, and that’s the best you can do,” he notes.

UL’s Haataja’s has a more pointed view: “We’ll find out what constitutes compliance the first time there’s an enforcement action.”

With so little information and so much at stake, several industry manufacturing sources say requests for technical data have been picking up.

A CALL FOR HARMONY
Curiously, many industry companies, including the larger ones, are only now taking seriously the passage of recycling legislation in several states in the U.S. Most of these acts take dead aim at eliminating lead by focusing heavily on computers and monitors.

The Consumer Electronics Association (CEA) and the CTIA, the wireless association, both fear their members will have to deal with potentially 50 different laws. That's why these groups have been lobbying for a national solution. But there has been little movement in Congress to act on the several proposed bills, all of which seem stuck in some Congressional committee.

Along with other industry trade groups, both associations anticipate that additional, possibly even more stringent, environmental laws covering the industry will come out of the EU and other major market regions.

"This \[RoHS\] is just the starting point," says Actel's Newell. Unfortunately, that may be true for some companies that may or may not have made the July 1 deadline.

"If you're going to make the RoHS deadline, you better be making lead-free products today," says TI's Romm, "which means you should have been working on it a year ago."

See associated figure

NEED MORE INFORMATION?

Actel Corp.
www.actel.com
Advanced Circuits
www.4pcb.com
Consumer Electronics Association
www.ce.org
CTIA
www.ctia.org
European Lead-Free Soldering Network
www.europeanleadfree.net
Hewlett-Packard
www.hp.com
IPC
www.ipc.org
JEDEC
www.jedec.org
National Physical Laboratory
www.npl.co.uk
Newark InOne
www.newarkinone.com
Raven Industries
www.ravenind.com
Solectron Corp.
www.solectron.com
Texas Instruments
www.ti.edu
Underwriters Laboratories
www.ul.com

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