Printed Electronics 2012 Berlin, Germany, 3-4 April 2012

Citation

Ling, J. (2012), "Printed Electronics 2012 Berlin, Germany, 3-4 April 2012", Circuit World, Vol. 38 No. 3. https://doi.org/10.1108/cw.2012.21738caa.018

Printed Electronics 2012 Berlin, Germany, 3-4 April 2012

Article Type: Conferences and exhibitions From: Circuit World, Volume 38, Issue 3

Day 1

It is a measure of the level of interest in, and the acceptance and application of, PE that the organisers of this event have, each year, had to go in search of a venue with the capacity to accommodate all those who wish to attend. This year they have alighted most successfully on the Estrel Conference Centre in the eastern part of the city of Berlin, and with just under 1,000 delegates attending, there was no doubt that the move from Düsseldorf was timely.

IDTechEx Chairman Dr Peter Harrop described how the printing techniques involved in PEs have multiplied to a full range, including roll to roll, and the applications diversify between military to consumer packaged goods. The onus is now on print, with lower costs, and where one layer may be replacing several layers; the strategy of “pull-through” marketing has been successful, and the trend is towards bigger investments, especially in OLEDs, and the acquisition trail is extensive. His estimate is for the 2022 PE market value of $60 billion, with leading market drivers being large area PEs.

Dr Sophie Laurenson of Abbot Diagnostics spoke about PE in the diagnostics industry. For those who were unaware of her company, which was founded in 1888 in Illinois, they have 90,000 employees worldwide, had a sales revenue of $39 billion in 2011, and spend $4 billion per annum on R&D, with the skills of no less than 7,000 scientists available. In the medical world, less than 1 percent of healthcare budgets are spent of diagnostics, but in this field it is the molecular and point of care areas which are seeing growth. There are three key market segments – core laboratory, point of care, and home monitoring. Point of care diagnostics tend to be portable instruments, hand-held, rather than huge laboratory kit, with low test throughput, and with reduced complexity. One example was with glucose testing, this is a $multi-million market, and in which PEs have been used to create sensors measuring sensitivity, in great volume at low cost. Three IVD processes were detailed – sample processing, analytical measurement, and informatics, and here PE have provided some innovative new sensors, which can measure amperometric, potentiometric, and voltametrically. Field effect transistors are also of great interest. Diagnostics is a growth industry for PEs, and she commented that her work on the subject had led her to prefer gold to silver as a conductive, it is better for the attachment of modules.

Dr Uwe Katzer of Proctor & Gamble had a paper entitled “Printed electronics meets Pampers”. Which might have been a bit optimistic. As usual we were shown the leadership brands, the corporate video, the shiny world full of smiley people, whose lives have been touched by and blessed by P&G products. Apparently we have Moments of Truth, the first is when we choose a P&G product; the second is when we are using it. The third moment of truth was presumably a look at the results, but that is not what he said. He did say that PE will innovate everyday life; using a sensor in an electronic toothbrush can protect teeth and gums, he suggested, by preventing us from pressing too hard. Gosh. There are unaddressed needs and unrecognised benefits from PE, which permits low cost solutions to deliver some added value, by making products more intelligent. He concluded by saying that P&G are connecting and developing as the world’s most innovative company. Identifying applications for PEs, and bringing them into mass production, are opportunities, which would appear to be a repeat of what he said last year. There was, in truth, nothing new under the sun that shines in the P&G world.

Dr Amalia Garnier of Schneider Electric introduced us to her company which has a large range of products used in energy supply, and a vision to make energy visible, where power in a building can be integrated to meet the global energy challenge. Energy management means the use of sensors, and sensors means the employment of PEs. This allows the benefit of additional intelligence at low cost, and how products can be personalised. She listed a list of specifications for PE, which included the ability to withstand a harsh environment, have between five and 20 years lifetime, work efficiently and reliably at operating temperatures of between −10°C to +60°C, with integration of stand-alone components; there are many unknowns here, and they do not fully understand the cost factors, but they see five to ten years in development, seeking safe solutions which have to meet standards which already been set; they are in it for the long term.

Organic Thin Film Transistors for flexible electronics was the title of a paper given by Dr Bonwen Koo of the Samsung Advanced Institute of Technology. Polymer film and e-paper, OLEDs, TFT, and organic TFT research are core activities at SAIT, combining nanotechnologies with new converging technologies for new business. They are pursuing at least 123 new technologies, and under PE they are using their R&D infrastructure for new business market creation, with printed intelligence being a mature product by 2020. He gave a very technical and detailed paper, which provided an insight into how a Korean company has in many fields quite overtaken the Japanese.

Dr Maikel van Hest of the National Renewable Energy Labs was surprised that no less than 16 metals were available to choose from for the manufacture of solar cells. Indium Tin Oxide (ITO) is interesting, but is indium necessary for high conductivity? They use a combination of metals and the basic properties of sputtered ITO were described. However, Indium Zinc Oxide (IZO) annealed in air showed 95 percent stability, and IZO is also stable after 30 days at 95 percent RH/85°C. Amorphous IZO on a CIGS PV showed excellent properties, and reducing costs is the key, said Drvan Heest, and inorganic solar cells are much sought after. Organic decomposition inks were described, and low cost materials were examined – silver is no longer as popular as it was; ink-jet application is feasible, where very narrow features are possible. Copper is also a good conductor, and they have worked with aluminium particle inks.

Printechnologics GmbH, has been very successful in metallisation, explained their MD Mr Sascha Voigt, and now they want to be successful in commercialisation, and he went on to explain how they were approaching the topic. Making excessive statements is not a good idea, it can lead to disappointments, and it raises consumer expectations. Customers do not buy technology, they buy solutions, and not always the best technology is successful. It needs commitment and motivation, working through flat command structures, whilst making staff part of a team, and rewarding success, with all concerned. You know when you have arrived when you have your first paying customer, then you know you are on the right track. They have a strong alliance with 3M and IBM, and now they have TouchCode. They have produced more than 25 million touchcodes, and are aiming at 100 million. TouchCode is an invisible code that can be read by a Smart phone, such as an iPad or iPhone. Their technology is licensed. Touchcode combines the security benefits of RFID tags with the low costs of QR codes. Touchcode does not replace anything; it adds value, and can be used in gaming, brand protection, consumer brands, media publishing and ticketing. It is a new communication standard.

E-ink Holdings have a very energetic CMO by the name of Mr Sriram Peruvemba, who sees a library in every backpack. His company makes electronic paper, and last year’s sales of this were over $1 billion. We all know there is a change taking place, but why? Libraries are large, the books are numerous, and heavy. There are 75,000 libraries in Europe alone, and 1 million world-wide; between them they hold 20 billion volumes. But, sadly, they are falling onto disuse. In the UK book borrowing has decreased by 35 percent, but the cost has risen by 39 percent, and 100 libraries closed in the UK last year, which says little for British literacy rates. But, claims Mr Peruvemba, they have been in decline since before the internet started. Whilst for most the printed book is still the most favourite medium, we spend more time on our laptops. Ideally, libraries should be mobile, should operate both indoors and outdoors, be in your pocket, be open 24/7, and be reliable at anytime, anywhere in the world, with support online.

What is taking their place is 320 dpi e-paper, the one that looks really good; e-text books are the learning books of the future, and for them there is a pull from Brazil, Russia, India and China (BRIC) as well as parts of Africa. E-book checkouts are up 200 percent since 2010. Music score on an e-reader? Yes, why not. It will not break. It will be perfect for schools. It is about the most convenient way to gain knowledge.

The man from Mars, Mr Gerbert Goes, gave the same paper this year as he did last year, so he was still worried that 90 percent of shoppers like chocolate, but 80 percent of shoppers avoid the chocolate aisle. They have not improved. He wanted to NAG them, viz. Notice, Attention, Get, once again, so attracting the shopper to the product is important. PE can make physical and mental availability come to life. If you present your product well, packaging adds value. You have to be in the right place, such as by the entrance or at the end of a gondola, as they call them. “Salience” is a new word to us, but it defines when a consumer notices, recognises and thinks of a brand in a buying situation. But you are not alone here, said Mr Goes, every other brand is shouting. So you need an edge. He talked about Subway, who make filled rolls, and claimed that what they sold was all about health! What with added salt and invisible sugar, that might be pushing it even for Mars. Salience can be driven by interaction, and PE makes interaction possible. Mars have made M&Ms interactive through cartoon characters. PE is a means to an end, said Mr Goes, but judging by what he said, in the last 12 months Mars do not appear to have embraced PE to provide the “salience” that the chocolate lover is supposed to have.

Frank Rehme was also here last year, on behalf of Metro Stores, for whom he is the man in charge of innovations. Retailing and trading is one of the oldest professions in the world, and we need new recipes all the time, as our lives change, as people live longer, as social mores are being broken; once people used to sell you an Encyclopaedia, now you can use Wikipedia for free. It is now 2012 and the customer is now more aware than ever before about pricing, he/she is more professional, they use Facebook, Twitter, and communicate strongly with each other. Decisions are the result of emotions. We appear to have been given an interesting talk about the psychology of shopping from Frank and about buying senses, but not a lot about how PEs can assist.

Decathlon SA is not an Olympic event, but a company who manufacture and sell electronic sports equipment. Their Mr Antoine Revise spoke about their trading company called. Oxylane, a local and online retailer, with 600 stores in 18 countries including Brazil, India and China. They employ 50,000 people, with half their sales in France and a €6 billion turnover. Their electronic sports products are all functional. Much of this equipment needs circuit boards for interconnection, but they are difficult to incorporate into a soft product; as are components; there are numerous opportunities for PEs in sports products, including tents, helmets, backpacks and t-shirts. Examples of projects include a new heart rate monitor, electronic socks, which can measure foot temperature and walking distance. In the future other projects will be realised, but here the availability of components for several years will be vital, as well the availability of innovative companies involved in the PE field. Decathlon appear to have taken the initiative, and not rely upon the supply side to resolve customers problems, but appoint their own people to discover what PE can, and cannot do, for them. P&G, Mars et al., take note.

Day 2

Conductors

Liquid X Printed Metals Inc. have Dr John Belot as their Chief Scientist, and he explained that his company, in focusing on conductors, have found a way to produce particle-free conductive inks, and use a variety of metals including platinum, and oxides, and, as he demonstrated, they have a rapid process of converting liquids to metals at 90°C. For this you can use e-beam, X-rays, as well as a thermal source. Their current inks have nanoparticles, or metal flakes, as a conductive medium. The demand is for metal films of high purity, at least 60 percent solids content, which are stable at room temperature, and soluble in a variety of low viscosity solvents, such as xylenes. Inks can be defined down to 10μ gaps and tracks, with excellent adhesion to a variety of substrates. Inks are stable, and the solutions can be variable, aqueous or alkaline, and are based on commercially available raw materials.

Silver inks are highly conductive and stable, as is gold as well, with a conductivity of 1×10⁷ Siemens/metre, and again these can be defined down to 15μ gaps and tracks. There is good surface roughness, too. Alloys of nanoparticles can be difficult to produce, so they have produced a blend of silver and gold, with the proportions of each determined by conductivity requirement and end use. This is a young start-up company as a spin-off from Carnegie Mellon University. Material costs were not mentioned.

Professor Katsuaki Suganuma from Osaka University in Japan spoke about silver-nano inks for application at room temperature. First written about in 2007, this is an ink-jet application process, which cures at 100°C. They also have a silver carboxylate ink for antennae. The ink-jet printed lines have high conductivity, and can be used on stretchable conductive materials. Inkjet printed narrow lines showed high resistivity with a concave shape, and he showed how temperature can be used to determine resolution. They also have a very thermally stable ink for polyimide film, with a resistance of 1 Ω/□. They also have stretchable conductive materials, using stretch and conductive fibres, consisting of silicone polymer and silver flakes, and a polyurethane elastomer with silver flake, conductive even when stretched by 600 percent.

Dr Paul Riep of Intrinsiq of Malvern came to talk to the delegates about inorganic nanoparticle materials. A spin-off from Qiniteq in Malvern, Worcestershire, it finds itself with an HQ in Rochester in the NY State but the work is done in Farnborough, Hampshire. With 20 years’ experience under their belts, Intrinsiq have full nanoparticle production facilities, scales from 5 to 100 nm, and their labs can cover printing, sintering, and testing. Silver has now become very expensive, so is there a better route? Could we use copper, which is low cost and available? Well, yes, if it did not oxidise. But they now have a copper ink which can be ink-jet applied, and they have coated the copper in a nano-organic material which provides more than nine months stability. It can be applied to polyimide, glass, silicone, with rapid and fast drying using photonic curing, pulsed broadband emission, and a laser-based system. 3.9μ line definition is both achievable and reproducible. You can use Xenon for high volume, and laser for single wavelength, and for thin lines. They are looking at applications in displays, antennae, OLEDS, with printing possible on PI, glass, PET and paper. Nickel ink works well, particularly on silicone. His company is looking for new partners to address new applications and opportunities. Intrinsiq can replace silver, it would seem.

Peter Giesen hails from the Holst Centre in The Netherlands. Technology for embedded conductive structures was his theme. They can inkjet; screen print, employ photolithography and roller coating on flexible substrates, for smart packaging and flexible OLEDs, which are bendable, dynamically flexible, and these capabilities can be scaled up. Conductive structures are needed for smart packaging, RFID antennae, and in the world of lighting it is needed for bus bars and shunts, and so to have them embedded is ideal. However, the way in which they are made is rather slow and rather expensive, so far. Peter went on to describe how R2R (reel-to-reel) fabrication would be set up, with a rotary screen printing unit, then a sintering unit, or u/v curing. Results so far have been excellent, with good production potential.

PEs manufacturing

Mr S. Morokoshi of the JNC Corporation was happy to share with the large audience information on their range of new UV inks for use as etching and plating resists for PCB manufacture, for ink-jet application, or for use as insulation materials for touch screens; the latter application due to its high transparency and heat resistance. Transparency is almost unaffected by heat over 230°C. They have an ink for fabricating micro lens, as well. Ink-jet needs no mask, and is suitable for high-mix low-volume work. They also have a range of polyimide inks and a surface treatment agent which also assists in determining the pattern to be created. The polyimide ink is used as an insulator on PCBs, and can be defined down to 30 μm line, with 30 μm gap. He recommended ink-jet printers from Unite in Korea and Fuji Film Dimatix are both good machines. So are many others.

NovaCentrix have Mr Kurt Schroder as their Chief Scientist, whose subject was Photonic Curing – viz. high temperature curing on low temperature materials. His company make nano-materials, and thus e-inks. He demonstrated how silver ink could be sintered in a millisecond on plastic film, and they progressed on to processing capability of photonic curing whereby high temperature curing can take place on low temperature substrates, with a 300 μs pulse length, yielding 1,000°C on a surface like PET without damaging it. They have a system called SimPulse, which allows the simulation of their PulseForge system, in which the user can control the temperature in each portion of the thin film stack. Metalon is a system whereby an ink can be converted to a metal, and this can be used in a RFID tag at a price significantly lower than that of silver.

Uwe Ditmar of the company Ohio Gravure Technologies Inc. explained that this company was formerly Daetwyler R&D, so it is just a name change. But a big one. Daetwyler have 30 years’ experience in gravure printing for the packaging industry; nowadays feature sizes below 5 μm are standard, so for the PE market they have a modified standard engraver, called Accupress. Gravure lends itself to PE really well, with both additive and subtractive deposition techniques giving resolutions of 50μ tracks, with a 50μ gap, Ohio also offers speciality printing through transcribe or hybrid engraving. Factory costs are comparable to other relatively cheap printing techniques, and they have a range of functional inks including conductive and dielectric. Gravure as a printing process is very accurate, has high resolution, and ink film thickness can be varied, and can be used for RFID, solar cells, batteries, OLEDs, touchscreens, LCD, plasma, and backplanes. Definition can come down to 5 μm cells, lines and spaces. Essentially it is a sheet-fed press, with a granite bed, and a camera system is included for alignment, for layer to layer registration.

Mr Klaus Schiffer of the OTB Group explained what Pixdro is. Understandably it is ink-jet printing that is the technology behind what this company does. Positive printing and negative printing, the latter is where the conductive track is deposited between two insulating walls, the walls then being etched away, with further additive processes being possible. A 20-micron track is the result. Examples of applications included contact structuring, masking, diffusion barrier, encapsulation, contact forming, and doped materials used in displays. Back contact structuring was described, as was selective emitter etch back, all by ink-jet printing, which is in full production nowadays. There are many different print heads available – Xaar, Spectra, Konica Minolta, Xerox, to name but a few. These will operate on single-pass, multi-pass and roll to roll machines, and are for X Y and vector printing. They offer a variety of machines for ink-jet printing, for research, or for mass production. They employ the new OCE (Canon) heads which are totally reliable even when a nozzle fails.

David Ramahi of Optomec had aerosol jet printing as his subject – his company is well-established in the field of additive manufacturing solutions, whereby materials are applied in very small geometries, and many companies buy their equipment for pilot lines, as well as for scaled-up manufacture. Aerosol will handle both high and low viscosity materials and allows for 3D printing, touch screen and display manufacturing, with highly conductive and narrow tracks, as well as embedded components. It is employed for MEMs packaging, enabling the vertical stacking of dies, and in OLED packaging; display and touch screen applications are normal, as is 3D printing, one example being an antenna on a nose cone, and a moulded interconnect device (MID) being directly printed. Aerosol jet is unique in that it can handle a very wide window of range of viscosities, and a range of printing formats from very small to very large, from planar to 3D.

David Johnson of Integration Technology shared with us his knowledge of U/V curing by LEDs. Formed in 2000, his company was concentrating on wide format U/V curing, and in 2011 formed an alliance with IST in Germany, and they are now their strategic partner, with 14 offices around the world. LED length is variable; 85 mm arc length is normal for ink-jet printing; UV LED now offers 60 W per cm² – LEDs are water-cooled, and can be up to 2.8 m long if required. U/V dosage is much more intense with LEDs, and there is also air-cooling, used in a multi-head installation, where they are mounted close together; wavelength is between 365 nm and 405 nm, with no ozone being generated. There is no infra-red, and uniform radiation across the exposure width; units have a long service life, are compact, and clean room compatible.

Kroenert GmbH & Co. KG. have Frank Schäfer as their sales director, and this is a company with over 100 years of experience in printing, of all types; now they have now moved into PEs, with a roll to roll process machine. They have machines which can be used for printing lithium batteries, RFIDs, and a plan for a machine for PEs was illustrated. Operating in a clean room environment, with web-tension free operation, with full registration control for layers, with U/V drying, a web speed of between 30 and 50 m/m, and drying temperatures which can go up to 500°C. The machines come with an ink reservoir, which can be heated, a stirrer, level sensor, and filter with micro-pump. Unwinding can be done in several ways; a variety of driers are available, plus laminators, web cleaning units, etc. Here is an organisation comprising three companies who have the printed part of PEs completely covered.

Closing keynotes

The final session of the conference had Mr Michael Peterson, the COO of Information Mediary Corporation in Canada to talk about using PE for ultra-smart packaging. With considerable ingenuity, and commendable foresight, they had designed a system that would tell you “when the last piece of chewing gum came out of a blister pack”. In a situation where a pharmaceutical company produces 15 million packages a year for clinical trials, and if you wanted to know how the trials went, and how the patient got on, then you need the package to talk to you. That can be done with an RFID tag, but it is even better if the tags are removable and reusable. IMC have therefore produced a system called Med-ic Smart. A smart inlay has the circuitry which, when a pill is dispensed, and a circuit broken by the removal of the pill, the fact is recorded, although the circuitry is concealed from the patient; understandably there are a number of production steps involved in getting this done. The battery has to have a life of three years. Three years is an indulgence, thought Michael, but for a very large company it avoids the tiresome exercise of rescheduling distribution! But whilst IMC produce the package at their place in Thailand, it is the customer who applies the tag, and despatch to wherever. This is a commercial venture which is going well, with 200,000 packages a year being ordered from one customer alone. It was fascinating to learn that once patients were aware that their daily medication was being monitored, they improved their intake, from 40 to 90 percent!

The Technical Research Institute TITV in Greiz was represented by Dr Wolfgang Schneibner, and they have completed their work on textile integrated sensor systems for car interiors. Entitled Seat-Sen, it is an intelligent system integrated into the textiles of the seat. Electrically conductive fibres used in textiles form the basis, with sensor fibres woven into the textile itself. This is homogeneous, but a hybrid can be done with fibres woven in. A polymer fibre called ELITEX is used with an elasticity of 7 percent without any change to electrical properties. The electrical fibres should not be stretched more than 50 percent or they deteriorate, however, they can be incorporated into car seats, to act as an occupancy sensor, and moisture and pressure can also be monitored in such a way. The automotive industry has embraced this new technology enthusiastically.

De La Rue Group R&D have the patient Dr Philip Cooper, he of an enquiring mind, in charge of their venture into PE. He has pursued a theme of Power in Paper – Functionality v. Enhancement – for some time now. How hard is it to get power into things?

Mr De La Rue went to London to print stamps some 200 years ago, and what his company does with paper is innovative, and this takes the form of passports, security cards, and currency. Counterfeiting is a permanent problem, and passports are difficult to make cheaply, and ID protection is now important. Brand protection is also interesting, and Dr Cooper though that the PE could help in at least three areas – forensic, inspection and the consumer – whilst delivering enhancement and security. There are complications – most batteries and PVs are too big, most features have to last for between two and ten years, and features have to operate over the life of the object. Then there is the cost.

Dr Cooper descended on the source of power as a starting point. With a mobile ‘phone you can get rectification up to 2.4 GHz (3G) using a Schottkey diode using inorganic material. From this you can provide an electrochemical display, with low voltage, using an aluminium antenna, with printed diodes. In fact a 3G phone will give off 1.5 v. Energy harvesting. These displays can be produced with the roll to roll manufacturing approach, and can be used to provide a check to see if something is genuine. If it is, then the product will tell you, by a signal on a label. Wines and spirits are under attack, as are expensive perfumes, pharmaceuticals, Tax Stamps, and Certificates of Authenticity. Such a simple PE label, confirming authenticity, would have wide acceptance.

To get matters to a conclusion, Dr Cooper and De La Rue need some partners in the PE field who can provide the thoughts and the expertise. He concluded that users will not pay for functionality alone, there has to be some enhancement and security. Both sound possible.

The final paper of the two days was delivered by Mr Pedro Barquinha from the New University of Lisbon, where he and his colleagues have been working on a project where paper is a substrate using oxide TFTs.

Transparent electronics are vital for displays, estimated to be an $87 billion market by 2020. The ways in which such displays could be produced are myriad, in flexible OLEDS, in high-end LCD displays. Oxide TFTs have matured rapidly over the years since they were developed, now there are n-type and p-type oxides, as well as sputtered Gallium Indium Zinc Oxide with lower oxygen content, which are more stable, and have less stress and better performance all round. Put a passivation layer around it and the performance is improved even more, with processing temperatures down to 200°C with p-type transistors. Solution-based oxide TFTs will however process at temperatures down to 95°C for indium oxide transistors, and work in this field continues. ZTO TFTS at the University have been produced by spin-coating, and stability is very close to that of sputtered materials, and with GIZO TFTs the temperatures are even lower, at 400°C. But can you do all this on paper?

Paper has many advantages, but for the TFT it is flexibility that really matters. Resistivity levels are close to those seen on glass, but in a joint project with the University of Cambridge they have created CMOS on paper using oxide FETs. Annealed at 150°C for 1 h, the results showed some encouraging results, but n-type TFTS would be better at these lower temperatures. They hope to have some results in the very near future.

Closing the conference, Dr Peter Harrop said that PEs Europe would return to the same venue in Berlin next year, at a date yet to be decided.

Conclusions

It was encouraging to see details of the work being done at The University of Cambridge on graphene, both for ink-jet printing, and for roller-coating on polymer to create, upon receipt of an electrical charge, a clear window where previously that had been an opaque one. Ink-jet printing of graphene, in the RFID application for example, is an obvious replacement for the much more expensive silver. They did deliver a paper on the subject, and one hopes that many were listening.

PE is becoming, albeit slowly, a commercial realisation for many companies, although it was a little dispiriting to see such companies as Mars and P&G, both with fairly banal presentations, displaying a lack of commitment with their own large resources to the potential of PE to their role in the respective FMCG markets. Dr Sophie Laurenson of Abbott Diagnostics showed the way, and to very good effect.

No less than 20 different disciplines were covered in the two days, with four tracks running in parallel, and the organisation was seamlessly efficient. Some of the specifics being presented in various papers were exciting and bode well for the future.

IDTechEx have found an entirely suitable venue for this show, and it is pleasing to see that they will return to Berlin next year, when numbers will doubtless be larger, along with the level of interest, and hopefully the bottom lines of many who are involved in this intriguing technology.

John LingAssociate Editor