Oct 8, 2004 Webcast

What it's about

“The ABCs of Lead-Free in Electronics Manufacturing” has been jointly developed by EPTAC Corporation, the leading electronics manufacturing training and consulting firm, Design Chain Associates LLC, the leading design chain consulting firm, and TTI the leading distributor of passive, interconnect, and electromechanical components.

What you'll learn

By viewing this Webcast you will get a better appreciation for the impact that “Lead-Free” is likely to have on your current business and on your manufacturing processes. If your company does not have plans in place today, or if you want to learn more about what others are doing, this is the Webcast for you.

The Webcast is no longer available for viewing. HOWEVER, we encourage you to download a copy of the presentation slides.
Slide Pack (1mb .pdf)
Also, please review the Questions & Answers listed below.

Answers From The Webcast Q&A Session

• The Directives
• What's Covered?
• How will the directives be enforced?
• How do I document compliance?
• Could I be exempt?
• What's not ?
• Planning for the transition.
• What can I expect for component availability and cost?
• What's happening with part numbers, marking, and labeling?
• Inventory Management
• Boards
• Components
• Tin Whiskers
• Solders
• Quality
• Processes
• Equipment

The Directives

What does RoHS stand for?

Ken: Restriction of Hazardous Substances.

What is WEEE?

Ken: The recycling and recovery directive or the Waste Electronic Electrical Equipment.

So is WEEE mainly the "producer's " responsibility?

Ken: Yes

We are a contract manufacturer for wiring harnesses. Does RoHS affect us?

Ken: You are obligated to comply with RoHS after July 1, 2006 for products you supply for sale in the EU or other countries that refer to RoHS. I would also expect to have MDS for your wiring harnesses.

Is there legislation discussion in U.S. government similar to ROHS or WEEE?

Ken: The NEPSI Web site has some information that can help answer your question. http://www.epa.gov/epaoswer/non-hw/reduce/epr/index.htm

What are the key dates for California and Maine?

Ken: The DCA Web site, www.designchainassociates.com, has links to the latest RoHS, WEEE Directives, California, Maine, as well as other helpful information.

Where can I go to find an overview of the relevant "legislation"?

Ken: The DCA web site, www.designchainassociates.com has links to the RoHS and WEEE Directives as well as other useful resources.

Where do I find more information on the limits for the various material percentages? Where do I find the most recent versions of the RoHS directive?

Ken: The DCA web site, www.designchainassociates.com, has links to the latest RoHS and WEEE Directives as well as other helpful information.

Is there a RoHS or WEEE Web site?

Ken: The DCA web site, www.designchainassociates.com, has links to the latest RoHS and WEEE Directives as well as other helpful information.

Where can you get an official WEEE logo?

Ken: I don't think that there is an official logo. I have seen companies use a recycling-type image.

How will companies that fall outside of WEEE and RoHS categories be impacted?

Ken: If your products fall outside of RoHS and WEEE you may still be impacted because your material suppliers will be converting their products for RoHS compliance.

What's covered?

What is the difference between RoHS and lead-free?

Ken: "Lead Free" usually refers to the absence of lead in component finishes or the use of lead free solders in the manufacturing process. RoHS specifically restricts the use of 6 materials and their related compounds, lead is one of the six materials.

Would using non-lead free parts with lead-free solder violate RoHS?

Ken: Yes it would.

In order to avoid an expensive engineering redesign, my company is thinking of making last-time-buys of (lead) components that would support our production builds for the next 3-4 years. Could we use these components after 2006?

Ken: No, all products placed on the market after July 1 2006 must comply with RoHS.

Does July 1, 2006 refer to when a specific product was manufactured or to when that product design was first introduced, sold, etc?

Ken: It refers to "put on the Market", has nothing to do with when it was designed or when it was manufactured.

If a product is manufactured prior to July 2006 and contains non-compliant parts, can that product be sold after July 2006?

Ken: No, a product that is not RoHS compliant cannot be placed on the market after July 1, 2006.

If your customer's product stays in the United States, do you still have to use lead free?

Ken: No you do not need to be lead free today.

Can you be more detailed with what "placed in market" means?

Ken: I might add to what I have already said that there is no "grandfather clause", existing products would need to be made RoHS compliant.

Will the directive permit lead if there is return or recycling pick-up program?

Ken: There are exemptions for lead in specific applications today. A return or recycling program will not give you an out.

Does "Put on market" mean that we can build and ship a part to Europe up until July 2006, and that we can also ship replacement parts for these in the future?

Ken: Products "put on the market" prior to July 1 2006, do not have to be RoHS compliant. For products "put on the market" after August 13, 2005, you must mark them with the crossed-out wheelie bin. You may also continue to ship, replacement parts that are not RoHS compliant, only for equipment "placed on the market" prior to July 1, 2006.

If a product has been put into the field, but has returned for refurbish and will be resold, does it need to be RoHS compliant?

Ken: No, if it was placed on the market prior to July 1 2006. Yes, if it was placed on the market after July 1 2006.

Is there any % of lead acceptable in this "lead free" directive?

Ken: Yes, there is an exemption list of applications as well as a limit of 0.1wt% per "Homogeneous Material" for lead and its compounds.

If components may have lead, once soldered with a lead free system, is the end result deemed lead free?

Leo: No.

Is DECA-BDE included in the PBDEs?

Ken: DCCA-BDE is included today, but this is current under review by TAC for an exemption.

Is there any chance (hope) that the RoHS deadline will be extended past July 2006?

Ken: Yes, anything is possible, but, I would not plan on it.

Who is the "producer" in the following scenario?

A product is manufactured by Company "A" in the United States, with that company's name on the product, and shipped to Company "B", a distributor in Europe. That distributor sells the product to a European customer.

Ken: The short answer is the Name on the product is the "producer." In your example I would say company "A" is placing the product on the EU market for the first time.

Would it be acceptable for me to send Pb'd spare parts to a customer and they put it in a system they purchased after July 1st, 2006?

Ken: No, you can't send a PB'd part to a customer for them to put into a system that they purchased after July 1, 2006.

If spare parts are ordered as end-of-life and are intended to cover the next 2-3 years, and we build past the cutoff date mentioned, are we faced with scrapping large material commitments already made to support product that may not be built until after the aforementioned manufacturing date?

Ken: The gating date for spare parts is the date that the end-product was "placed on market" , not the build date. You can supply spare parts that are not RoHS compliant to repair systems placed on the market prior to July 1, 2006.

Please clarify the use of spare part sub-assemblies (boards) as it relates to RoHS and WEEE.

Ken: Spare part sub-assemblies that are not in compliance with RoHS may be used to repair products placed on the market prior to July 1, 2006. The WEEE directive applies to end products, so there is no impact to sub-assemblies, unless your customers pass along some responsibility for take back as part of their contract to you.

What's the smallest component of an IC that is considered homogeneous?

Ken: The finish on the leads and the die attach material are some examples.

Enforcement

How will the Directives be enforced? Who will be policing these new directives?

Ken: The policing will vary from country to country.

Can an EU country adopt the RoHS legislation "in part", or must they all adopt it "in full". (i.e. only lead, but not cadmium etc.)

Ken: They need to adopt it in full. How they do the actual implementation may be different from country to country. The material limits established in RoHS will be the same for all countries.

How are EU companies handling this transition?

Ken: Not any better than the U.S. companies. This is a challenge for all of us.

Have the EU member states put these directives into law yet, with definite enforcement dates?

Ken: NO, at this point in time most EU countries have not passed the directives into their country laws.

Article 9 of the WEEE allows member states to alternatively put the financial responsibility on the users as opposed to the producers. Has this been determined by the member states yet?

Ken: NO, most member states have not transformed the directives into law in their countries.

What are the penalties for shipping a leaded assembly into the EU after July 1, 2006?

Ken: Removal of product from the market, fines, or imprisonment of corporate officers. The last action being the least probable.

What will be the consequences if the supplier does not comply with lead free regulations?

Ken: Removal of product from the market, fines, or imprisonment of corporate officers. The last action being the least probable.

Documentation

How do I document my compliance and that of my suppliers? What reporting method(s) is acceptable to the governing bodies in the EU?

Ken: This is no standard reporting method in place today.

Who/what organizations will be authorized to validate RoHs and WEEE initiative compliance?

Ken: The individual EU countries will determine how they do this.

How do we indicate RoHS compliance for components if exemptions based on applications are exempt?

Ken: You do not need to do anything if your product is RoHS exempt, but you need to comply with the WEEE Directive.

Are material declarations needed for each homogeneous part of an IC?

Ken: All homogeneous materials used to make an IC should be included in a Material Declaration.

If an OEM supplies a sub-product that has violated the % of those elements, who is responsible for the Materials Declaration since you might rely on the information supplied from the OEM?

Ken: The responsibility would ultimately fall on the "producer" of the product. Most products are the result of an integration of "sub Products" from many OEMs. That is why is it is some important to insist on complete and accurate Material Declaration sheets.

How will a material declaration be possible given that some manufacturers have changed to a non-lead termination without changing their part number (ceramic capacitors)?

Ken: The new part, having the same part number, will be associated with a Product Change Notification (PCN) that has a unique tracking number. I suggest that the MDS be associated with this or any other unique identifier, which in some cases would be date code.

With respect to component compliance to RoHS, will there need to be documentation per shipment, or will an initial declaration be considered sufficient as due diligence?

Ken: Initial documentation of component homogeneous material content should be sufficient as long as there is a process in place to track changes and update the MDS if necessary.

Is the labeling of materials with the crossed-out wheelie bin required for equipment released before 8/05?

Ken: Products "put on the market" after 8/05 will need to have the crossed-out wheelie bin. There are currently discussions to establish the requirements for the marking.

Can we get a copy of a template for the material declaration sheet that Ken showed?

Ken: Regarding your request for a copy of our material declaration form, please call us at 866-DCA-7676. Our form is designed to meet our needs, which may not reflect your needs. We would like to speak with you about your requirements so we can better understand what your needs are.

Are the Material Declaration forms government-created forms, do OEMs themselves create the forms?

Ken: MDS are not government forms and there currently exists no standard form. There are several formats that are being used today, the DCA form being a very good example.

What certification methods or approvals will be in place to guarantee lead free? It seems each OEM is responsible to say it is lead free. That makes it easy to lie.

Ken: When a producer places its product on the market after July 1 2006, it "self-declares" its compliance. You need to make sure you have completed your due diligence and have a MDS to demonstrate compliance if you are challenged.

What end-product markings will be required or proposed?

Ken: Products "put on the market" after 8/05 will need to have the crossed-out wheelie bin. There are currently discussions to establish the requirements for the marking.

Is a copy of the Material Declaration Record available?

Ken: Regarding your request for a copy of our material declaration form, please call us at 866-DCA-7676. Our form is designed to meet our needs, which may not reflect your needs. We would like to speak with you about your requirements so we can better understand what your needs are.

How would we create a material declaration record beyond the component supplier's data sheet with compliance guaranteed?

Ken: There are quite a few packages and services available. What's best for your company is dependent upon what your needs are. DCA can help you through the decision process.

As a non-franchised distributor what responsibility do we have to our customers for providing material declarations for products we sell to them?

Ken: None, unless you want to pass along this information as a value added service to your customers.

If your product and its end-application are exempt, how is this to be indicated for shipments?

Ken: You do not need to do anything if your product is RoHS exempt, but, you need to comply with the WEEE Directive.

Have you seen requirements for material safety data sheets for products sold to EU companies?

Ken: MSDS have been and will continue to be requested by some companies. MSDS do not replace the need for Material Data Sheets.

Could I be exempt? Is my [company, product, application] exempt from RoHS and WEEE?

There were many questions asking if particular products and applications are exempt from RoHS and WEEE. I have answered most of these below. In addition, I have posted two decision trees and the detailed categories on the DCA Web site at http://www.designchainassociates.com/hazmat.html. Please check that information if you have questions about possible exemptions.

Exempted

• If an EMS builds the product for anOEM the EMS is not the "producer". If it builds and sells the product under its own product label, it is the "producer".
• RoHS & WEEE do not apply to products that are greater than 1500 volts DC (such a high voltage DC power supplies).
• Batteries are not part of the RoHS and WEEE Directives; they fall under the battery directive.
• Military products are exempt from RoHS requirements, but be careful. This is a direct use item only. Some examples are arms, bombs, munitions.
• Generators used for military purposes are exempt.
• Note that direct military products do not fall under WEEE or RoHS, but as the military has pushed the use of commercial off-the-shelf (COTS) components they will have to resolve significant issues such as Tin Whiskers and reliability. I don't see many manufacturers continuing to offer both traditional lead finishes and "lead free" finishes.
• RoHS and WEEE do not cover the automotive industry (including automotive aftermarket products). But, those products need to comply the the ELV directive to sell in the EU.

Not Exempted

• Even if an IC is encapsulated, it is not considered compliant if internal solder is Pb'd. However, there is an exemption for high temperature solder.
• The directives apply to wire, cables, and connectors not on boards.

Is lead embedded in a component acceptable? (i.e. lead in glass component bodies, etc.)

Ken: There are exceptions, and lead in ceramic body of capacitors is another good example.

Is a potted product a homogeneous one?

Ken: NO, it can be "Mechanically Disjointed"

Is it possible to have a lead free design EXCEPT for one main component (12x12 240 pin BGA with 0.5mm pitch)? This is a cell phone design.

Ken: This is currently a request for exemption that the TAC is investigating, stay tuned.

How is avionics affected?

Ken: I'll need more specifics to answer your question.

It is my understanding that this only applies to commercial products and not to industrial. Is this correct?

Ken: I would look to the product categories to determine what applies and what is not included in the scope of the Directives.

We are a small manufacturer of electronic instrumentation for industrial measurement applications. How does the Feb 2005 review effect us in regards to selling instrumentation into the EU?

Ken: I would need more details on the specifics of your products for a complete answer, but in general I would say that you will need a "take back" scheme.

I manufacture a test instrument designed 35 years ago using thru hole components used by can factories around the world. Since the instruments last for decades, I only ship around 10 to 15 new units each year. Do I have to redesign this product using surface mount, Pb-free materials?

Ken: Yes, you need to use materials that are RoHS Compliant if you sell to the EU Countries.

Planning for the Transition

Is there an available format for an (already created) Environmental Compliance Plan?

Ken: There is no standard format, as you might expect, the plan is determined by the needs of the each business. Design Chain Associates has the resources to assist your company in the development and execution of an Environmental compliance plan.

What would you suggest -after education-would be the next 2 steps to take at this point in preparation for compliance?

Ken: Executive management support and a company wide Project Team and Plan.

Is there a guide book available that companies can use to start a transition program?

Ken: No, not that I know of. But, as we said in the Webcast, there are resources that can help you, DCA, EPTAC, and TTI.

Is it correct to assume that a piecemeal approach is impractical? In other words, do all components and the board all have to be lead free?

Ken: Yes, you are correct.

What are the top problems considered to set up this program?

Ken: If I understand the question correctly, I would list in this order, 1. A Corporate Position; 2. Executive sponsor; 3. Project plan; and, 4. Funding (resources, time and money).

Is a template available for manufacturers to follow to facilitate conversion to lead-free?

Ken: There is no standard format, as you might expect, the plan is determined by the needs of the each business. Design Chain Associates has the resources to assist your company in the development and execution of an Environmental compliance plan.

Are OEMs required to dissect each BOM part by part to identify lead-free call outs? High mix EMS providers are concerned with the front end work associated with item master updates. Any check lists available for a stream-lined process?

Ken: Yes, OEMs must be able to prove that their products are in compliance with RoHS. Unfortunately there are no cheap and quick methods to collect the MDS Data or to scrub a BOM for RoHS compliance. There are third parties who can help extend your resources --Design Chain Associates is one such company.

Do you know of any consulting companies that can help our company with both the WEEE and RoHS directives

Ken: Yes, DCA (www.designchainassociates.com) and EPTAC (www.eptac.com).

Where/how can U.S. producers (manufacturers/distributors) find collection/recycling centers in the EU?

Ken: We have no recommendations at this time.

Availability and Cost

Will [RoHS and WEEE compliance] affect the actual cost of the parts? Do you see component prices increasing?

Ken: So far we have seen little if any impact to part cost. This could change over time as the cost of Tin continues to rise. There may also be some short term market imbalances as the 2006 deadline approaches. Ultimately, price changes will be up to the individual suppliers.

Do you have any guidance on the change in part cost and manufacturing transformation cost in 2005 & 2006?

Ken: I can talk to part cost, so far we have seen little if any impact to part cost. This could change over time as the cost of Tin continues to rise.

Will manufacturers continue to offer parts in dual packages or will the Tin Lead packages be phased out? If so when?

Ken: Most suppliers will phase out Tin Lead finishes, the timetable will vary by supplier.

How will the lead times for RoHS components vary as 2006 approaches?

Melanie: Realistically, there may be some lead-time issues until full production occurs at the component factories during 2005, but that's about all.

What is the risk of current leaded parts not being available as non-lead parts?

Melanie: It is all based on expected demand. Some commercial component manufacturers will not continue to produce both leaded and lead-free parts but will only supply lead-free. Our product management team will have to assess your BOM to offer logical part alternatives with your buyers and engineers.

Ken: Most components will be able to convert to RoHS compliant. The manufacturers will be granted exceptions on a case by case basis. For example, high temp lead solder used as a die attach for power transistors is exempt.

Do any or some vendors plan to have concurrent production of lead and lead-free components?

Melanie: It is a mixed bag. Some will continue to offer both product types if the demand is high enough; others will not.

Are there a lot of companies supplying lead-free components? Second sourcing components has been an issue, especially dealing with specialized products.

Melanie: Several commercial resistor and capacitor manufacturers have been providing a lead-free component for many years. For them, the issue is whether or not the product meets the other hazmat restrictions under RoHS. Our product marketing group at the branch can help you convert to suppliers that are currently offering lead-free parts and also, work with you over the next 6-12 months to convert to RoHS compliant parts as more factories begin manufacturing them. In cases where a supplier is not creating a new part number, we will have to rely on the part label as the best means to identify compliant parts in your inventory.

I have 3000 products to change over to RoHS compliance by the end of 2005. I am pushing TTI and others to supply RoHS/lead-free components now, but availability is still an issue from the manufacturers. Is TTI pushing back to the manufacturers? I would like to have all of my components changed over by the end of 2004, but this looks to be almost impossible. Does TTI have many customers pushing for RoHS compliant parts?

Melanie: TTI has been in the process of converting our inventory over to the reformulated components for the past year. However, we face the same issues as our end customers do: Reduction of our existing inventory to customers not requiring RoHS parts at this time; reduction of existing inventory at the component manufacturer; and managing new production schedules at the component manufacturer for each individual reformulated component.

TTI and NEDA are requesting a documented, effective plan to convert to RoHS compliant parts as quickly as possible and have asked the component manufacturers to utilize the RoHS compliance spreadsheet format as the basis for communication with us to keep us all informed of the schedule. The spreadsheet is posted on our web site.

At this time we estimate that 50% of the products that require conversion to the EU Directives are now available. We think that the balance of resistors and capacitors will be available by June 2005. Connector products as a whole probably won't be totally available until January, 2006 due to their complexity. Don't forget, the conversion to lead-free products must be done in a timely manner, but customers
must be very careful to make sure their production processes are adjusted to accommodate the part parameters before converting to the RoHS parts (i.e. increased reflow, preheat, cool-down temps and times, solder flux changes, board cleaning changes, etc.)

Part numbers, marking, and labeling

Will part numbers change? What percentage of component manufacturers have committed to changing their part numbers?

Melanie: At this time about 50 % of the manufacturers are changing part numbers. The others are concerned about the file maintenance impact of adding additional part numbers to their data base, additional inventory storage requirements due to more bin locations, or lost print position at customers because of backlogging drawing changes.

The part numbers will change only for those component manufacturers who have elected to create a new part number for the reformulated parts. The rest of the manufacturers will not. The only way to identify the parts with the same nomenclature will be through the label marking, date or lot code change, etc.

Ken: Not all suppliers are changing part numbers, but most suppliers will do so. And most consumers will change their internal part numbers as well.

How strong is your recommendation on new internal part numbers for lead free parts?

Ken: Very strong. In the short term you will be managing both RoHS compliant and non-compliant parts.

How can any component manufacturer justify changing component termination finishes without changing their part numbers...considering the impact on production processes and the ultimate end-user impact on system reliability?

Melanie: When the component suppliers started their transition planning two or more years ago, most inputs from the customers indicated that a new part number would be more of a problem than the resultant re-qualifications and updates to part drawings. We now believe the reverse is true. Ironically, we are having much more success with the suppliers who have started their transition plans much more recently since they had not already made the part number decision.

How is TTI managing suppliers that will not change their part numbers to identify lead free parts?

Melanie: Our first priority is to convince component manufacturers that a part number change for the reformulated part is essential for managing the transition effectively. For those manufacturers that cannot change part numbers, we are requiring that the unit container labels on the parts display an industry accepted identification system similar to the ones proposed by JEITA and JEDEC. TTI will create separate bin locations and internal part numbers to manage both formulations and will require our sales branches to specify the correct part nomenclature on the sales order to provide the customer with the appropriate part.

Is there any organization that will enforce part number changes?

Ken: There are standards and guidelines (see JEDEC, NEDA), but there are no organizations that will enforce part number change.

What do you know about the JEDEC standard (for marking) in development, which used E1 thru E7 and G1 thru G7? Is this happening and will everyone use it?

Ken: Yes this is a standard and, like all standards, it will be up to the purchasing contract to drive compliance. Not all suppliers are using it today.

Are you aware of newly published JESD97 standard for Pb-free marking of parts and packaging?

Leo: I am aware of the document titled JES097. I have not reviewed it at this point but I plan to near term.

Will TTI (and/or the whole industry) do if suppliers don't change their part numbers? Will TTI change its internal part numbers?

Melanie: TTI will determine a systemized solution for managing the transition regardless of the factory decisions. We may consider creating internal part numbers so we can maintain separate inventories for compliant and non-compliant parts. However, this may not be the optimum solution for all products. Physical separation of the inventory is critical.

The whole distribution industry is still developing solutions. Our primary method will be to identify the product at incoming inspection as compliant product via part labeling identifiers and setting up separate internal locations for inventory purposes.

How much influence does NEDA have on manufacturer marking for Lead Free/RoHS compliance?

Melanie: NEDA as a standards generating organization does not have regulatory control with our suppliers. But, as business partners and as customers we all have influence. The fact that all key global distributors are speaking with one voice has significant impact on the suppliers' decisions. Of course, OEM's such as yourselves have as much influence, perhaps even more. Make sure you are requiring part number changes with your component manufacturers.

Melanie: Have any of the component manufacturers formally addressed the NEDA paper? Is there a manufacturers association that is likely to address this?

Melanie: Several key component manufacturers are on the NEDA committee addressing and supporting the lead-free/RoHS white paper. Some of these component manufacturers are re-evaluating their plans as they understand the evolving situation better. In the final analysis, each company will make its decisions based on what is best for their position in the market place. It is our role to make sure they understand the consequences of those decisions and help them adjust their positions with better information from all of us.

Inventory Management

What should I do if I currently have only non lead-free components in stock, and then have to build lead-free products? Would I throw away old stock?

Ken: No, why throw away 'GOOD Parts"?! RoHS does not impact products placed on the market prior to July 1, 2006 and there are many other uses that will not be impacted.

How will TTI handle the return of non-compliant components after they have established compliant inventory?

Melanie: We will scrap parts out or put them in separate bin locations so they will not be mixed with compliant inventory.

What about existing inventories at transition time?

Melanie: One of the most complex areas for distributors to manage is keeping the on-hand inventories correct during the transition period. TTI is addressing this issue and is still developing solutions. We will resolve it but we will need to work closely with our customers to assure we provide the correct parts.

Melanie: Yes. TTI is tracking the lead-free status of all parts in our inventory. We don't set that indicator until we manually confirm that our entire on-hand inventory is compliant.

Will TTI share the lead-free indicators with its customers?

Melanie: Yes, starting in Q1 2005 customers will be able to see that indicator when they do a stock inquiry on our Web site. Parts will indicate "Lead-free Yes" for those parts which are lead-free and "Lead-free No" for parts numbers which are not.

Later in 2005, TTI will add a Yes/No indicator for RoHS compliance. What is TTI's definition of Pb-free, as indicated by its flag?

Melanie: Product is with Pb levels acceptable to RoHS %.

Will data dissemination occur on the TTI website or is there another method, such as email?

Melanie: The best way to provide factory information available to all customers is via our web site. We have set up a special, Lead Free section within the MarketEye area of our site. It is updated daily and we indicate new updates by factory each week.

Boards

What is the minimum and ideal Tg for Pb free PCB's?

Leo: Standard FR4 material has a Tg of approximately 125 degrees Fahrenheit. This works but many are going to higher Tg material to accommodate the higher process temperature.

What PCB materials have qualified lead free process?

Leo: Qualified PCB materials are truly not defined. Many are still working to qualify their existing materials.

Does going to lead-free solder require any changes to PCB layouts?

Leo: PCB layouts should look at specific pad sizes to make sure they can accommodate the poor flow of lead free solder paste. Keep in mind pad sizes for SMT components, which are going to be wave soldered. Since the lead free solder is more viscous than the leaded solder, larger pad sizes may be necessary to allow the solder to contact the pad and make the solder joint. One should also look at extra pads for multi leaded components to help the pad back and prevent shorts at the last lead on the component.

How important will the correct pad size be for components?

Leo: Pad sizes are going to be important for good wetting and paste volume control.

The PCB Fabrication change from Immersion Silver to Immersion gold; has this been made as a result of the lead-free process?

Leo: All immersion coatings were designed for flatter surfaces for surface mount components. HASL coatings had uneven pads and created co-planarity problems with the surface mount components.

Which is the most popular board finish in the industry at this time in regards to lead free?

Leo: It appears that Electroless Nickel Immersion Gold (ENIG) is being the one many companies are going to. Check with your board supplier to see what is the one of choice for its customers.

Are most terminations going towards matte tin?

Leo: Lead free terminations are typically going to Electroless Nickel Immersion Gold (ENIG), Hand Gold Plating, Immersion Tin, Immersion Silver, and of course OSP.

I was told by polyclad that Td of 350 should be the call out on you FR4 material. Is this true?

Leo: Thermal decomposition temperature is still an unknown. Many labs are working to see if this has any impact on the dielectric constant of the laminate material.

Is there data available regarding which thermoplastics (i.e. PBT, PA, PPA, LCP) meet lead free soldering conditions (JEDEC STD201)?

Leo: Data for thermoplastics to meet the thermal excursion of the product should be available from the suppliers.

Will EU directives also be driving halogen-free laminate requirements?

Leo: As far as I know Halogen-free laminate is still being investigated as a substitute for bromides for fire retardant boards.

Components

Can older, lead-based components be used in a lead-free process?

Leo: Yes, both can happen and this is called backwards and forward compatibility. The thermal processes are going to be very important to get good metal melt at both the lead and board interface.

Can lead-free packages with leads be used in a leaded wave solder process?

Leo: Documents on backward compatibility of components are not generally available, but will have to be acquired from the component suppliers.

Will the electronic characteristics of high frequency components change if a component has lead free leads compared with components that have leaded leads?

Ken: No, I don't see a component's high frequency characteristics being changed by the switch to "lead Free". You may see an impact to the PCB as a result of using different board materials.

Is there a standard categorization change required for moisture sensitivity? (JEDEC STD22B) Acceptance standards or workmanship standards? (IPCA610) (IPC600) (STD-001)

Leo: The suppliers are still investigating moisture sensitive levels. As we mentioned, the change due to increased process temperatures may have an effect on them.

When is the next revision of IPC-A-610 with lead-free acceptance criteria going to be released?

Leo: The IPC is looking to get release of IPC-A-610 and J-STD-001 by APEX 2005 in February 2005.

Is there any formal standard for component (raw material) identification?

Leo: There is no formal standard for raw component identification. Material declaration sheets will be the start. You will need to push back on your suppliers to get this information.

Are you familiar with [Automotive Industry Action Group]AIAG formats?

Leo: No, we are not currently familiar with any AIAG formats. Please provide us with the information if that is at all possible.

Tin Whiskers

What is the effect of conformal coatings on tin whiskers?

Leo: Again many questions were asked relative to tin whiskers, such as where do they come from, are they impacted by conformal coating, will tin over Nickel help prevent the whiskers and such.

Tin whiskers come from the tin plating and all indications seem to point to the stress levels within the tin plating as the causes, however, they cannot be reproduced at will and it takes a long time for the whisker to grow. Regardless of the base material, the whisker comes from the tin plating and any application of conformal coating will not prevent any whiskers from being created, as the whiskers will grow through the conformal coating.

What is the best method for testing for tin whiskers?

Leo: Tin whiskers test methods can be found on the NEMI web page (http://www.nemi.org/projects/ese/tin_whisker_activities.html).

All of these tests are still being investigated to determine which one is the best to create the whisker in a predictable fashion.

What magnification is needed to see tin whiskers?

Leo: Typical 10x to 40x inspection magnification will allow one to see the tin whiskers.

Is there anyone addressing the tin whiskers problem? Will there be additional problems of current leakage with the new solder fluxes in an environment of high humidity?

Leo: Tin whiskers are definitely an issue and the industry will once again have to be very cautious as to the when and where they happen.

Won't suppliers for Avionics and Aerospace still make lead products which will avoid any "tin whiskers?"

Ken: Tin Whiskers are a major concern for the entire electronics industry and especially the Avionics and Aerospace segments. The switch to "lead Free" will certainly cause supply issues as the availability of lead finish parts decreases.

Solders

Are their any manufacturers offering compliant solders, today?

Leo: All solder suppliers offer different types of lead free solders and fluxes.

What is the difference between solder temp profiles of leaded vs. lead-free? 20C? More or less?

Leo: The typical temperature difference between the existing tin/lead solder and the new SAC alloys is about 30 to 40 degrees C.

Will high tin solder attack the materials that current solder pots are made of?

Leo: I think you're asking, Will the equipment be subjected to more deterioration due to the higher tin content solders? It depends upon the material the existing pot are made of, however going to lead-free solders will require the installation of new solder pots. Using the old pots will not be acceptable as the old pots are contaminated with the lead from the old solder.

What about using conductive epoxy in place of solder?

Leo: Conductive epoxies have been reviewed in the past but were found to loose their conductivity over a period of time. Perhaps new investigations could prove otherwise.

Japan is using Bi bearing solders. The large majority of Japanese sourced electrolytics have 3% Bi in the plating. What is the effect on reliability of SnPb assembly (during the transition to Pb-free)?

Leo: The use of Bi allows the use of lower temperatures in the process. The reliability is still being evaluated and is not determined at this point in time.

Is there a possibility that there may eventually be a lead free alternative with lower solder temp requirements? Some unleaded solders have lower transitions temps than tin/lead solder. Why can't we use lower temperature solders?

Leo: The potential of a lead free material with lower soldering temperature is definitely possible, however, as of today, those materials are still being evaluated. Lower transition temperature solders or low temperature solders have to be evaluated for all the requisites of the product. Yes, lower temperature solders can be used but will they be as strong in both tensile and shear strength as the existing material? Will they also be as compliant as the existing material and will they be as inert as today materials? All these questions have to be answered to satisfy the requirements of the product.

Is no-clean flux still used with lead free?

Leo: No-clean fluxes or low solid content fluxes may be designed for lead-free processes but you would have to check with the suppliers to make sure you are using the materials correctly.

Aren't some of the alloys being considered to replace lead worse than lead for the environment?

Leo: Environmentally some materials may be worst for the environment, but that is a discussion that is too large for this forum at this point.

What about other long-term reliability issues with brittle solder joints

Leo: Brittleness is an issue and needs to be checked for any impact to the process and product reliability.

Has anyone looked at the reliability of the lead-free solder joint?

Leo: Many questions were asked relative to whether the solder joints will be as strong, whether the joint be of the same integrity as the existing ones, whether the joints be stronger than the existing leaded solder joints, and asking what are the risks of using lead-free components with leaded solder. All these answers are not available at this time. People are working the issues, however long-term reliability testing is expensive and time consuming, and not many people are working to provide those answers. Many companies will have to conduct those evaluations to provide levels of comfort on the long-term reliability of their products.

Quality

How do these requirements affect test requirements?

Leo: Test requirements will have to be designed to accommodate the new lead free processes, of which is more than can be answered in this space.

Are there any reliability studies done on the lead-free reliability?

Leo: Reliability studies at this point in time are being conducted but the information is not currently available. People are not sharing the results, perhaps keeping the information confidential to gain a competitive advantage.

When components in equipment change to lead-free, do you recommend that the final product be completely retested for reliability, HALT (highly accelerated life testing) and ESS (environmental stress screening) testing?

Leo: All reliability tests should be conducted on the products as the solder alloy is changed to lead free.

Processes

Would you be able to solder lead parts with lead-free paste, and vice versa?

Leo: Many questions were asked relative to soldering lead parts with lead free solder. Please read this carefully as there are many variations to this answer.

• Lead-free parts can be soldered with leaded solder paste, but the reflow temperatures may not be high enough to get good solder flow on the lead-free lead, which could impact the various classes of acceptance for solder wetting at the heel of the lead.
• Lead-free parts can be soldered in a leaded solder pot, but the wetting may not be as good as it is with leaded parts.
• Leaded parts can be soldered with lead-free solder paste and this will be conducted at higher temperatures
• Leaded parts cannot be soldered with lead-free solder in the solder pot, as you will contaminate the solder in the solder pot.

Does going to lead-free solder require any changes to solder paste screens?

Leo: At this point in time, I don't believe any changes will be required of the stencils when depositing lead free solder paste. Basically the only difference is the alloy of the solder balls and the viscosity agents in the paste. No one has mentioned that this is a concern.

What temperature do you recommend for your solder pot for SAC alloys?

Leo: Solder pot temperatures for lead free solders may be about 260° to 265° C.

Is the compatibility a concern between the component termination plating and the lead-free solder paste?

Leo: One should pay attention to the compatibility of the lead plating material and the physical solder alloy being used. Having both being similar makes the process more consistent.

What is the typical peak reflow temperature that one should target using a SAC305 alloy?

Leo: The peak reflow temperature would be 40° to 50° degrees higher than the liquidus temperature of the solder alloy. If the liquidus temperature is 219, then I would set the top reflow process around 259° to 269° C.

How are cleaning processes affected by the WEEE and RoHS directives? In other words, will no-clean fluxes be mandated?

Leo: WEEE and RoHS will not dictate the fluxes to be used. Soldering quality will determine the fluxes to be used.

How will high temperature affect plastic components on the board?

Ken: Components in general and those that contain plastic must be qualified for the higher processing temperatures, or be hand assembled.

Are all current TTI lead-free components backward compatible with the leaded process?

Melanie: Lead-free components may or may not be backward compatible based on your PCB process. You can view each supplier's current information to this question by viewing their lead free information on the TTI Web site (http://www.ttiinc.com/page/ME_LF.html).

Are the actual test methods for polybrominated compounds standardized? Where can we find methods?

Ken: The test methods for testing have not been agreed to by the EU. That said there are efforts underway by NEMI to establish a standard method. I would suggest that XRF be considered for polybrominated compounds.

How do I find a Contract Manufacturer in my area that can make a lead free PWB assembly for my company?

Ken: There are many listings for Contract Manufacturers that can be found on the Web or various electronic publications.

Equipment

Can today's equipment support temperatures required for PB-free soldering process (e.g. reflow ovens)?

Leo: Current equipment should have the capability to reach reflow temperatures; however, the total ramp up temperatures and cool down temperatures will need to be monitored closely to make sure they can have an acceptable thermal profile. Shorter four-stage ovens may have some problems depending on the thermal mass of the product.

What Soldering Iron manufacturers have tips for irons?

Leo: Solder Iron Tips – You will have to contact the major iron suppliers such as Pace, Metcal, Weller, Hexacon, and of course Plato for starters.

You mentioned replacing the solder pot. Do you mean just certain components such as pumps and flow ducts or the entire pot itself?

Leo: Solder pot replacement means all items, which currently have come into contact with the tin-lead solder. You cannot use existing solder pots.

How will changing components such as motor and fans affect UL and CE certifications? Will equipment need to be recertified?

Leo: Equipment may need to be recertified, but I cannot see this affecting any UL or CE requirements.

How will board-cleaning systems be affected by the directive?

Leo: The equipment should not be affected from a process perspective; however, controls may be more stringent.