SMART Group Annual Conference Spread Eagle Hotel, Thame, UK 2-3 October

Article Type: Conferences and exhibitions From: Soldering & Surface Mount Technology, Volume 26, Issue 1

The many delegates were warmly welcomed by the Chairman, Mr Keith Bryant, who does warm welcomes very well indeed. SMART Group does a huge amount of good to the European electronics industry, from lead-free down to cleaning, understanding tin whiskers, and has been at the vanguard of imparting technical training, knowledge and experience to their subscribers. Their SMART-e-Link is a world-wide forum; they have hundreds of members, and provide solutions to problems based on shared knowledge. They always have an eye on the future, and are looking at all manner of topics suggested by their members. Quite where the assembly industry in the UK would be without the SMART Group is a matter of gloomy speculation.

As with all good conferences, it is the table-top exhibitors who make many things possible, and so each one was given a brief moment in time to introduce themselves and what they did, do, and will be doing. The exhibitors include Fraser, ALR Services, Heraeus, Loctite, DKL Metals Ltd, Indium Corporation, GEN Systems, Zestron, Nordson Dage and Chemical Watch, a company producing a service providers’ guide.

Mr Richard Holden is the Head of Manufacturing at Lloyds Bank. He gave us an overview of what his bank is doing to support UK manufacturing. Banks have not always enjoyed a good press, and they do not always have a good track record in supporting British manufacturing. Lloyds Bank went out and spoke to industry, and were told that banks do not understand manufacturers, they had no knowledgeable managers, had no understanding of investment cycles and supply chains, and, in summary, they were very much off course.

So, in conjunction with the EEF, WTA and WMG they have established a five-day training programme at The University of Warwick on what is required of a bank dealing with manufacturers, which includes 20 hours of post-module assignment. They want to add value, understand the work flow, talk to the people on the shop floor, understand the markets being served, and the demands that those markets make upon suppliers. Working with their own internal and external partners and specialists they have now embarked upon a £1 billion lending commitment to manufacturers, and they reached that target within nine months. Net lending to SMEs went up by 5 per cent last year against a national average of −3 per cent and at Lloyds Bank eight out of ten overdraft requests are approved.

Lloyds Bank provides support on products, finance options, cash flow management, manufacturing industry insight, sharing best practice, and he gave is an interesting case study of a company who were unable to honour export contracts as their production machinery would not cope, so a capital expenditure case was based on asset lending and invoice funding, plus help with export finance through FCGD. The finance was collected, the machinery purchased, the contracts honoured, and the client company is now trading profitably and increasingly with customers in China.

There are some other areas of comment – skills shortage, we need more engineers, new and emerging markets – exports have not risen as much as they might have done, especially to areas such as BRIC and CIVETS*. It is never been cheaper to raise finance from banks, which is good, and much of recovery is based, as it always has been, on increasing confidence.

Note: *Colombia, Venezuela, Indonesia, Egypt, Turkey and South Africa.

Mr Gareth Jones is the Senior Manager at Sony UK Technology Centre in Pencoed, South Wales. They have been there since 1973, when Sony made TVs in the UK, some 15,000 a day. Back in the 1980s they ran out of capacity at Bridgend and relocated to Pencoed. All of this ceased in 2005, as flat-screen TVs were already being manufactured in Spain and Eastern Europe, so the Pencoed plant needed a change of course. So they diversified considerably in 2000, manufacturing outside broadcast cameras (at £15,000 each) and signal transmission mixing decks. They have a service centre and technical information centre, and a contract electronic manufacturing centre, which is where the Raspberry Pi, a mini-computer, is built. They have a collaborative manufacturing service, along with professional solutions manufacturing, and so nowadays they offer a very diverse business operation. Bringing manufacturing back to the UK is called re-shoring, and this is what has happened with the Raspberry Pi. The key areas of change were influenced by several factors: the need for working capital, for having a stable supply chain, and operational support, and sales support. Within these headings there are many strong reasons why a move inwards is good – in China there had been increasing costs due to wage inflation, a long and inflexible supply chain, poor delivery achievement due to labour instability, and too much engineering support cost.

Pencoed were able to show much more attractive labour costs, perfect delivery, no skills gap, good PR, no language barrier in communication, and sales and supply support in all aspects. The image of made in the UK carries a lot of weight, too.

They have just made their first million, and they are sold through RS Components and Parnells. We heard more about Raspberry Pi later in the day.

Professor Martin Goosey, Chairman of the Institute of Circuit Technology (amongst many other things), presented the topic of environmental legislation and resources utilisation. Martin spent 35 years working on electronic materials, and became interested in environmentally friendly materials as a result. He touched upon the work done within the IeMRC, which organisation is also involved with such things. Established in 2004, it has a £16 million research funding from EPSRC, and research is carried out within >30 UK institute and universities, and work will continue through to 2015, all of which is research in the field of electronics. It is all about research through to commercial exploitation, with a lot of industrial support, and successful bids attract TSB funding for work through to commercial launch.

Electronics uses materials that are toxic and potentially harmful to the environment. Growing pressure from consumers to make products safer led to the introduction of WEEE in Europe, and an overall desire to adopt more sustainable approaches. Electronic waste was, and still is, going to African countries for “re-cycling” with adverse consequences.

There are more than a few elements and compounds that can cause problems, such as cadmium, cyanide, silver, mercury, lead, brominated flame retardants, chromium, antimony, etc. The Restriction of Hazardous Substances (RoHS) covers all the five elements and compounds that are deemed hazardous, such as hexavalent chromium, mercury, etc. The impact of RoHS with lead had a severe impact on the electronics industry as lead was no longer an ingredient in solders (apart for solders for military applications which are exempt). Most lead is used outside the electronics industry (less than 0.5 per cent within it), and it is relatively easy to recover. Initial compliance with RoHS cost the industry $32 billion by 2008, and the industry is still looking for alloys which will provide the same security of soldering offered by tin/lead. All sorts of gremlins have appeared or have been exacerbated by lead-free, such as CAF, tin-whiskers, and solder joint failures.

Brominated Flame retardants have been proscribed by RoHS, except when they are used in PCBs. Laminate suppliers are now ordering a range of halogen-free laminate, using phosphorous-base flame retardants, which offer some benefits but also raise the price of the base material.

Companies have used RoHS to improve their supply chain status, and in this regard have benefitted from legislation by compliance. Legislation does give opportunities for innovation, but someone has to pay for it all.

There are several elements, including helium, phosphorous, indium and gallium, for which demand will exceed supply, and rare earths are pretty much within the control of China, which has raised concerns. There are elements which are critical for electronics which include tellurium (semiconductors), hafnium (dielectric), tantalum (capacitors), indium (for ITO for displays), gallium (compound semiconductors), and dysprosium (magnets). Demand will exceed supply for gallium and indium, and dysprosium, which allows magnets to work at higher temperatures, will see demand increasing, too.

Martin concluded with a look at the research work being done within the IeMRC family, and this includes sustainable electronics, power supplies, and whisker mitigation at Loughborough, which has been very successful and is close to commercial application. At Leicester they are developing a flux-less soldering process using ionic liquids. They have obtained good wetting across a variety of substrates and these include nickel, copper, brass, stainless steel, it is water-washable, and they can solder on them all.

Change=cost, and compliance has incurred huge costs, and much work is on-going to accommodate the legislation. Does it all make sense? It depends where you are looking from.

For further information, please contact: mgoosey@lboro.ac.uk

Gary Nevison is the Head of Legislation and Compliance at Farnell – RoHS was his subject, and he looked initially at RoHS and the difference between RoHS1 and RoHS2. There have been some changes to the wording, the number of product categories have increased, notably in medical devices and monitor and control equipment.

Development boards are regarded as being within the scope of EEE by the authorities, but not by the Raspberry Pi Foundation who use development boards, which are not a single-board computer. The European Commission terminology for development kits does not seem to apply to Raspberry Pi. “Dev Kits” are not finished equipment, are they?

There is a new scope under RoHS for cables, and there are a host of guidance notes for Annexes III and IV under exemptions and exclusions. The latter includes military/aerospace; transport; implantable medical devices; and lawnmowers.

Declarations of conformity should best be signed by technical directors of a company rather than the CEO. The CE mark is the only indication of compliance.

It takes a very special person to get his head around RoHS legislation, and the translation of the tortuous use of the English language by the legislators, so it is little wonder that Mr Nevison is regarded as the interpretation guru for the benefit of his colleagues in the industry. They are lucky to have him.

For further information, please contact: gnevison@farnell.com

Martin Baxter is the Director of Policy of the Institute of Environmental Management and Assessment (IEMA).

Delivering business value through EMS revision to ISO 14001

It is all subject to change! The changes have implications for all management system standards. Happily all ISO’s work is done in English. ISO 14001 has been taken up by 267,000 certified organisations in 158 countries in Asia and Europe. The highest is China, we are fifth. A study group report on EMS made 24 recommendations for improvement, which will then meet the needs of business and the environment to the mid-2020s. ISO have adopted a new common structure for all of its management system standards. It uses common clause titles, numbering, content, terms and definitions, and it is the outcome, not the system that is focused upon.

The new structure will include, under the context of the organisation, an understanding of the organisation and its context. An understanding of the needs and expectation of interested parties. Leadership and commitment also appears as a title. Other new titles include:

* Actions to address risks and opportunities.

* Risks and opportunities arising from environmental aspects.

* External communication and reporting.

* Under operation – value chain planning and control.

* Under improvement – continual improvement.

* Context, leadership and EMS scope.

The overall context is a new requirement, and it requires organisations to consider a broad range of internal and external factors, external environmental impact on the organisation, and determining the expectations of interested parties, including those outside the organisation. Under leadership, there are enhanced requirements for top management involvement, and environmental performance or be considered in strategic planning.

One should also broaden the range of policy commitments to include biodiversity, sustainable use of natural resources, climate change adaptations.

The application of ISO 14001 is to risks and opportunities, not just the environmental impact of the organisation, but also he link to other business risks. The value chain perspective should also be considered – and there is more emphasis on performance improvement, and being able to demonstrate environmental outcomes, and a greater requirement for determining communication needs.

In summary – there will be a broader focus, more external focus, integration into core business process, and demonstrate environmental performance.

All of this will be published in May 2015. In the period 2012-2015 the committee for ISO will have met in Berlin, Bangkok, Gothenburg, Botswana, Bogota, and somewhere else nice in Europe. "Life is a book, and those who do not travel will only have read one chapter", as the saying goes. ISO is a bit more than a few chapters.

For further information, please contact: m.baxter@iema.net

Roger Rogowski spoke about counterfeiting in the electronics supply chain. He is with the UKEA a body of trade associations representing the UK electronics sector. It brings to the attention of senior government ministers matters relating to the UK electronics industry under one banner, and membership of UKEA includes IMAPS, SMART Group, Connect, etc.

There were 1,363 cases of counterfeit incidents reported in 2011. In the USA, there were 1,800 cases in the DoD supply chain alone, and 57 per cent of these were obsolete.

The components might be factory rejects, they may have a different die inside than what is wanted, they might be marked as more expensive part, they can come from reclaimed scrap, they can be re-marked, there can be copyright infringements, there is the use of stolen designs, and counterfeiting applies to almost every component type from amplifiers to transistors.

There is a huge number of organisations worldwide whose aim is to rid the planet of such people. BEAMA, ESIA, IPO, the MoD counterfeit avoidance group, and the UKEA anti-counterfeiting forum are amongst them.

Information providers include:ERAI: http://www.erai.cm

GIDEP: http://www.gidep.org

HIS: http://www.ihs.com

UKEA Anti-counterfeiting Forum (available FOC): http://www.anticounterfetingforum.com

Dr Jeremy Smallwood spoke about profiting from knowledge and experience in ESD control, about which he knows all there is to know, running, as he does, a company called Electrostatic Solutions Ltd Many components or assemblies are susceptible to ESD damage, semiconductors, PCBs containing ESDS, and modules. ESDS (sensitive devices) must be protected from damage, and you should really only handle them in an ESD area.

The cost of inadequate protection is considerable – product failures, failure in analysis and test, the need to rework, the need to overstock, production delay, ones company’s reputation, and an upset customer.

There are controls, of course. BS EN/IEC61340-5-1 and ESD S20:20. This is in use world-wide and is widely respected. However, it is not always well understood. Compliance is beneficial, customer acceptance being one.

One’s own company should have an ESD programme plan, including training and compliance verification. Good documentation is a key requirement. He and his company can assist in writing this plan, and appoint a coordinator.

Cutting costs – the costs include planning and development of the ESD control programme, documentation, EPA equipment and control measures protective packaging, training, compliance verification, and performance evaluation. But, argued Dr Smallwood, these costs are in fact investments, investments in security, reliability, yield, performance, and reputation. Such controls applied with knowledge and understanding can be an excellent investment.

If you have inadequate specifications with your ESD programme, and you give inadequate training, and there is inadequate verification, then you may be cutting cost too fine. He gave some examples of where money had not been spent wisely in the assembly rooms, and where on the face of it ESD control looked good, but was seriously defective in grounding personnel.

To optimise investment, minimise handling.

EPA – electrostatic protected area. Ensure EPAs occupy a minimum area, not a maximum.

ESD technology road map shows that ESDS are becoming ever more sensitive, excellent controls are need to handle them, and the controls in place yesterday will certainly not be good enough for tomorrow.

ESD is a subject that might often be given lip-service, but the need to take the matter more seriously is now vital.

Day 2-3 October 2013

Sue Knight welcomed everyone to the second day, and thanked the committee for all their hard work in making the event possible, and for the excellent administration. Being a modest soul, she made no mention of her own role in making the SMART Group what it is.

The first speaker of the day was Dr Dominic Lodge, Manager of the Solder Technology Division at ITRI, and Leader of the Soldertec Network.

50 per cent of tin that is used is used in solder with 35,000 tons of bar, and 25,000 tons of wire lead-free solder used each year. ITRI have their ITSCI initiative which ensures that tin comes from conflict free areas in the Congo. Low cost lead-free solders have been produced for the Chinese market, it is patent-free, and they have been looking at low-temperature solders for reduced energy use. They melt at lower temperatures, and zinc and bismuth are vital ingredients. There are few viable alternatives to high temperature solders, and as everything is getting smaller, and more powerful, and less expensive, so components are getting smaller, as are their joints, now 2-9 μm. Tin-lead is decreasing, albeit slowly.

SAC305 and SAC405 have a low melting point 217°C, and it is a eutectic. Additives include silver, because it wets well, but it has a high price, which fluctuates, but it does reduce the drop shock relevant to mobile phones.

SN100C, SACX, SACM, FENIX 100, all are low silver solders, with lower cost, and there are some advantages in reducing the silver content. It reduces the copper corrosion, but the disadvantages are that it introduces a "pasty range" and increases copper dissolution. Nickel, however reduces this, and retards IMC growth, but more than 0.05 per cent increases rewetting. Bi is a good additive for strength and reliability, P and Ge both reduce oxidation in the wave, and Ge improves solder flow. For reliability, higher silver alloys perform better in thermal cycling tests, but the long term reliability of lead-free solders is still a concern. Innolot is a good product for the automotive market. Undergoing research are lower silver alloys, with comparable data, and reliability data, as well as high reliability solders, which may include nanocomposites, and new low energy process technologies.

Mr Keith Sweatman has been in the industry for 40 years, and is with Nihon Superior as their Senior Technical Advisor.

The balance between economics and solder selection is a fine one, as he illustrated. Where are we now? SAC 405 and SAC305, with increasing low SAC and no SAC, for reflow, but for wave and selective there is a strong trend away from SAC305 and DSAC405. The same, too, for hand soldering and rework.

Back in the 1990 a US Senator took up the fight to have lead banned in solders, or no more than 0.1 per cent b/w. The electronics industry went into shock, but happily any legislation confined such restrictions to plumbing solder. But the message was clear, and lead-free did in the end come to haunt the surface mount industry. Back in 1994 the IDEALS project in Europe homed in on SAC387. In 1998 the EU issued the second draft of a directive, and IDEALS and NEMI got together with a list of recommendations for solders for various applications. IPC said that SAC305 would be the lead-free alloy of choice for the industry. JEITA then recommended SAC107 and SAC0307.

Key considerations now are failure mechanisms. Thermal cycling tests show strain in areas of highest shear stress, and there is failure in accelerated thermal cycling, where the cracks propagate in the re-crystallisation area.

It seems that it is now getting so complicated in the world of lead-free that the universally acceptable solder alloy has yet to be found, and a return to lead-free would save the industry a ton of money and make assembled boards more reliable. After all, was there any scientific evidence produced to explain why lead should be banned? None.

High reliability Pb-free alloys was the subject of Mr Richard Boyle, who is the wonderfully titled Global Technical Champion at Henkel. There has to be a silver cup somewhere. It is the need for high reliability in a wide temperature range, and working at lower temperatures that he spoke about. Zero failures for 30 years would be good, say the car makers and this does drive the technology on. The German Government were keen on this and supported the Innolot Project, which was all about looking at SAC alloys to see what was available. Reliability at higher temperatures was the aim, against tin/lead at 80°C, and Innolot at 150°C. Alloying elements with SAC were listed as Bismuth, Sb, and Ni. Creep strength was reduced with the addition of Ni, but Bi and Sb increased it, and pre-alloyed solder was preferred. The alloy was patented, Heraeus and Cookson and Henkel were all involved, and so there was not much benefit for the industry. The yield stress for this material was much higher than any other SAC variations, and less failures at temperature cycling than others, such as SAC387 and SN63. 90iSC Innolot material showed the same vibration resistance as tin/lead, but was better than SAC305. Halogen free materials are now demanded, conflict metals is a strong subject and Richard was reassuring that high reliability did not mean high cost.

It seems to be the case that assembly companies dedicate a huge amount of time and research into determining the right SAC solder for their purposes, and which meets their customers’ specifications. Having found that product, they tend to stick with it. The hardest part would be the sifting through the innumerable products, and assessing them. If there is an industry standard it is SAC305, but it is not for everyone. Innolot is a highly reliable Pb-free alloy.

Martin Wickham from NPL has been around for a long time, but tin has been around for a lot longer; 4,000 years at least. Innovation is what NPL is all about, and they are pushing the boundaries for solder to see what is possible. High temperature electronics are essential, in terms of energy saving in application, especially in the field of silicon carbide. Sintering metal powders means that Ag can be used for die bonding and at 285°C for 60 minutes, 20 nm material after sintering looks very cohesive. ELCOSINt is another project involved with using silver nano-silver based materials to form joints between components and substrates.

Low temperature interconnect is another big area for NPL. Printed electronics is one of these, on plastic and film, typically printing at below 150°C, ideally below 100°C, and the printing process can include litho, gravure, flexo and screen. Inkjet is another medium for application, in large area displays, flexibles, OLEDs, and organic PVs. Martin looked at printed paper products, smart labelling, RFID, anti-counterfeiting, large area sensor arrays, flexible electronics, and conductive fabric, using a cotton fibre through the weave. Conductive adhesives are generally Ag loaded, and they are some issues with the formation of Sn oxide at the adhesive component interface. Reusable unzippable sustainable electronics is another NPL project, as is roll-to-roll PE, and what they call ReUSE electronics. There are some busy people down in Teddington.

Pete Lomas is the dynamic Co-Founder and Trustee of the Raspberry Pi Foundation and came along to tell us why this product came about. And how.

The genesis of the problem that Raspberry Pi was aimed at was that school students thought that studying/understanding computers was perceived as hard, and geeky. Students opted for the "soft" subjects such as golf course management, and film-making, with the result that there are now less than 3,000 students in electrical engineering accepting degree places, from 5,000 ten years ago. It is a disaster waiting to happen. Mr Dyson took his R&D to Singapore and filled it immediately with 600 qualified engineers, which he could not have done in the UK.

Students at school: are they consumers or creators? Building up an understanding of how products do what they do was what the Raspberry Pi Foundation was set up to address, and to further the advancement of education of adults and children, particularly in the field of computers. They were to be cheap enough to break, and basic enough to understand. The only place they could go to have it built at a very low price was China. But their experience showed that having things made in China is not the sinecure. Poor QC control, sheer distance, cultural differences, all counted against China.

When Raspberry Pi was launched they sold 10,000 in the first 10 minutes, with a projection for 250,000 more. So, their distributors, Farnell, said we should re-shore it, it will make life easier, and that is why they went to Sony Technology Ltd in the UK.

They understood the PoP design, and they understood scalable technology, and they understood quality. They had a collaborative "Can do" attitude.

The name came from the fact that most electronic equipment is now named after a fruit, and the Pi comes from the language. So far the number sold exceeds 1.8 million, and Mr Lomas felt strongly that we should be repatriating as much as we can, and we should encourage our children to become the engineers of tomorrow.

Stewart McCracken of MCS came to talk about electronics failure analysis. MCS have some new techniques for improved process yield by a non-destructive test method called Broad Ion Beam (BIB), and this can be employed on all solderable finishes. The traditional method is to take a micro-section, encapsulate the sample in resin, which is ground, and then polished down to the target interface required; this, by and large, works well enough. But when you compare this to a cross-section taken by BIB preparation, much more is revealed. There is no deformation, no smearing, you get a true microstructure and both surface and x-section; indeed an accurate analysis is available with some real results.

The sharp non-deformed edges allow accurate thickness measurement, and there is no mechanical contact. The system uses three large ∼1 mm ion beams to strip/sputter away the exposed sample. It can be used for solderable coatings, where a very clear measurable image is produced, with accurate layer thickness, and the copper microstructure is revealed, so that high resolution element mapping is possible. This technique can be used to cross-section solder-balls, wire bonds and white residues to enable far greater image sharpness and visibility allowing for accurate scanning electron microscope and element dispersive X-ray analysis.

A very exciting improvement on failure analysis, and can likened to some strong light in a previously darkened room.

The final session of the conference was devoted to the science and technology of cleaning electronic assemblies after soldering and began with SMART Group Vice Chairman Graham Naisbitt, MD of Gen3 Systems whose title was "To clean or not to clean?". Although the perceived primary advantages of running a no-clean process were to save money and space by eliminating a process, Graham Naisbitt made it clear that some cleaning was inevitable anyway and the perception of cost saving through not cleaning was misguided. Cleaning would actually save money by improving end product reliability and reducing field returns.

Through ESCO, the British Electronics Systems Community, Graham had proposed a collaborative project which would qualify for government-funded support and which would be carried out by an institution such as the Materials Technology Centre, which had the appropriate equipment and skills.

Martin Königer, Senior Process Engineer with Zestron, emphasised the need for effective process monitoring and control of bath parameters, whatever actual process was chosen, to ensure consistency in operation. He reviewed indirect methods for measurement of cleaning agent concentration. Straightforward test kits were available based on colorimetry, or refractive index or conductivity measurement. "The cleaning process is only as good as its monitoring!" But whatever technique was used for controlling the process line, the definitive measure of its performance was the cleanliness and freedom from ionic contamination of the product. Königer reviewed IPC, ISO and J-STD standard test methods and commented upon their limitations, particularly that isopropanol was not necessarily a good solvent for extracting ionic material.

The final speaker was Mike Bixenman from Kyzen Corporation who gave advice on how to design a batch cleaning process for electronic assemblies as demands for performance and reliability continued to increase. The primary considerations in designing a cleaning process were to start with a cleanable solder paste, then to make sure the reflow process was under control, then select a cleaning agent that matched the soil and the intended cleaning equipment. The cleaning machine itself was probably the main driver in making decisions. Mike Bixenman used an Ishikawa diagram, with the main branches headed PCB design, solder paste or flux, cleaning agent and cleaning machine, to illustrate all the process factors to be taken into consideration in order to achieve the ideal cleaning condition of no unwanted visible or ionic residue on the surface or under the components.

Six categories of soldering material to be taken into account in the selection of "cleanable soils" were SMT solder paste, SMT solder flux, wave-solder bar, wave-solder flux, rework solder wire and rework solder flux, because these would directly impact the cleaning process. Besides higher reflow temperatures, consequences of the move to lead-free soldering included the requirement for higher fluxing capacity, and higher molecular weight flux resins, some with polymer additives.

The general result was that residues were harder to clean. "Soluble soils clean better" was a statement of the obvious, but a pointer towards careful matching the cleaning agent to the nature of the residue as well as to the machinery, where considerations of concentration, temperature, pressure, speed, rinsing and drying were all important factors. Optimisation of spray impingement and avoidance of shadowing were critical to achieving effective cleaning under large and low-stand-off components.

SMART Group have once again constructed and managed a very informative and useful conference, with a range of subjects that were designed to provide something for everyone, which is always a very good plan.

John Ling

Associate Editor