Get back to basics with ROHS Compliance
Faster chips, increasing investment in R&D, lower costs and the continuing implications of Moore's Law on the growth of the semiconductor industry are just a few of the big issues senior management have had to contend with in recent years. And while these top-level agenda items are not about to disappear, there's a new issue that should be on every senior managers' radar in the lead up to Summer 2006; RoHS - the latest piece of environmental legislation to emanate from those nice people in Brussels. RoHS is one of those issues that seems to be everywhere. It's been the topic of countless seminars and articles and is ubiquitous on the internet, where claims of "RoHS compliant" components or design packages abound.
Like it or not, RoHS now forms a major part of many electrical or electronic engineers' working lives. The worrying thing about this overload of RoHS information is the apparent lack of practical experience of actually manufacturing RoHS compliant PCBs - and the impact on the manufacturing supply chain. In short, most people who need to understand about the legislation have read the leaflets and ticked the boxes. But true compliance is much more complicated than that. Our experience working with the semiconductor market shows that there are still too many designers out there who have simply seen RoHS as ‘a product that contains no lead', and that by ticking the "materials must be RoHS compliant" box, they assume that their product becomes compliant. This is dangerous thinking, as mere adherence to the letter of RoHS legislation, may well be creating huge problems further down the track.
RoHS - otherwise known as EU Directive 2002/95/EC, Restriction of Hazardous Substances - is the latest environmental overture from the EU and comes into force in July of next year. The directive has already been implemented in a number of other European countries and seeks to effectively ban six toxic substances from electrical and electronic products. These substances are lead, mercury, cadmium, hexavelant chromium, polybrominated biphenyls and polybrominated diphenyl ethers.
For Exception PCB, the implementation of the directive has brought our relationships with both suppliers and customers into sharp focus. While our finished PCBs have been lead-free for some time now, the critical point is what happens after they leave our plant. RoHS has encouraged us to find out more about how our PCBs are being utilised and enhanced further down the manufacturing chain. Similarly, the legislation is prompting OEM customers to think more carefully about the functionality of the boards and their suitability to achieve RoHS compliance. This last point has proven vitally important in many of our conversations with semiconductor and other OEM manufacturers.
To illustrate the point, let's firstly look at the components of a PCB and how players in the manufacturing supply chain interface to deliver a finished product. Previously, a designer from an OEM manufacturer would send over their drawings for a certain quantity of PCBs to be manufactured to a specific quality by an agreed time. We would then produce the required product, following detailed requirements outlined in the designs. With the advent of RoHS, that relatively simple relationship between designer and supplier has been turned on its head. Designers, aware of the fact that they need to meet environmental compliance standards now add the note into their designs that "all materials must be compliant", without realising that the necessary adoption of lead-free alternatives has had huge knock-on effects onto other materials used in the manufacturing process. While a designer may be right to tick the "compliance required" box on his submitted drawings, we are aware of instances where adopting the letter of the law and blindly adopting lead-free solders in isolation would be tantamount to product suicide. In reality, adhering to the designer's RoHSfriendly specifications would create a fully compliant, but totally flawed product. The reason being that laminates – even those that pass the stringent FR4 test for quality - are generally unable to withstand the much higher temperatures required to work with lead-free solders. Hence, FR4 standard laminates, as specified by designers looking for the best quality boards, would find their RoHS compliant PCBs suffering from the effects of Z axis expansion during assembly as well as potential board decomposition. Even if the boards survive the assembly process, the potential for failure in the field is vastly increased. We have worked closely with a number of laminate suppliers - including Isola and Polyclad - to understand the demands lead-free manufacturing places on laminates. Having identified the issues, we have worked closely with designers and helped to create a "virtuous community" so that vital knowledge on laminates is understood by all in the manufacturing supply chain.
Designers in the semiconductor sector need to understand that RoHS compliance is vitally important, but cannot be adhered to with a simple tick box mentality. OEMs that have sorted their compliance issues out are characterised by the fact that they have established ongoing dialogue with their suppliers to understand the RoHS issue from every angle. Electronics designers that get the most from their suppliers are those that step back and take the time to consider the end application of a component. What type of board do we really want? What function does it have and under what sort of tolerances must it operate? These are the type of questions that should be asked when reevaluating designs.
Exporting the problem of RoHS can only create problems further down the supply chain and lead to disagreements and conflict. We should be treating the challenge of environmental compliance as an opportunity to work together - and not promulgate the "silo" mentality that will only encourage conflict. RoHS does put additional pressures on electrical designers and engineers. But if it encourages them to go back to the basics of product design - and open up a genuine dialogue with their suppliers and customers - it can only be a good thing.
