Printed Electronics Europe 2006, Churchill College, Cambridge, UK, 20 and 21 April 2006

Citation

Ling, J. (2006), "Printed Electronics Europe 2006, Churchill College, Cambridge, UK, 20 and 21 April 2006", Soldering & Surface Mount Technology, Vol. 18 No. 3. https://doi.org/10.1108/ssmt.2006.21918cac.001

Printed Electronics Europe 2006, Churchill College, Cambridge, UK, 20 and 21 April 2006

Printed Electronics Europe 2006, Churchill College, Cambridge, UK, 20 and 21 April 2006

Keywords: Keywords Electronics industry, Manufacturing, Printed-circuit boards, Conferences

It might be supposed that a headline writer would have put down something like “The Dawning of a New Age” if he had attended the conference held at Churchill College, Cambridge, on 20 and 21 April 2006. He would have only been half right. In fact the dawn broke last year when IDTechEx held their first Printed Electronics Europe Conference at the same place. Since, then interest has grown apace. In fact at such a pace that the Wolfson Theatre was filled to capacity and extra chairs had to be brought into allow 235 delegates to see what was going on (Plate 1).

Plate 1 Wolfson Theatre, Churchill College, Cambridge

Raghu Das, CEO of IDTechEX welcomed them all, numbers being 30 per cent up on last year. At that rate a new venue will need to be found. However, that is a problem for later. For now – what exactly is printed electronics? Definition: they are thin layers of material produced mainly by printing techniques and used for electrical and electronic purposes; they are laminar alternatives to conventional electronic and electrical components and interconnects.

Printed electronics is a $300 billion opportunity. In 20 years from now it will be twice the size of the silicon industry to-day. It will replace lighting, it will replace many things, as we were to discover. Last year IDTEchEX held their first Printed Electronics Conference in the USA. Then only OLEDs were discussed; now there are five other display technologies to discuss. Many more companies have joined this sector, and new examples included a 40-inch single OLED sheet from Samsung, analogue signal processing with organic PET's by Infineon in Germany; the University of California has developed printed nose sensors for consumer packaging, the University of Tokyo has produced organic PET for Braille displays.

The market for OLEDs in the display market was $500 million in 2005, and it is only concerns about yield and reliability (and longevity) that inhibits wider applications.

OLEDS can be used as hoardings, where the ads can change, and.OLEDS can be used in laptops, they are more secure. Samsung have high hopes for OLED screens, they are planning to ship 20 million units next year, rising to 50 million by 2008.

Some 10 trillion barcodes have been replaced with a RFID tag, at about 1cent a tag. RFID could be printed directly onto the product, in time, but chip RFID won't go down below 1cent – yet. Other activities include electrophoretic displays – good for e-books, notebooks; photodetector and OFETS, for organic sensors; actuators and OFETS for Braille displays; TFTCs – thin film transistor circuits for memory applications including RFID, and TFTCs come in two varieties – small molecule (insoluble) and large molecule (soluble), and here Dainippon is strong.

So what are some of the new products that hinge around printed electronics? Pressure sensors + OFETS have enabled a device which measures skin temperature; a “cell” phone can now be used as a ticket, as a means of ATM; there is Audio Paper from Toppan Forms which plays back a written message powered by a printed battery; the idea of being spoken to by a packet of soap powder is certainly novel, but one can see huge applications for product end use.

By 2025 the potential market for printed electronics is estimated to be worth $250 billion.

Dan Lawrence is the VP for Business Development for IDTechEX in the USA and he gave us an update on the North American markets. In the states all regions are busy identifying opportunities, funding the research, and marketing the products, to a greater or lesser extent. In Europe there has been great response, in Scandinavia as well, and also in Australia and New Zealand. North America has strong academic and industrial research, a novel venture capital climate, segmented government support, a strong and well-financed printing industry, large semiconductor manufacturers, and of course a major market.

VC fundraising has now reached $31.4billion investment in start-ups, new businesses, aimed at electronics. He mentioned the “Tweens” market which is where 8-12-year-old spend $170 billion a year; not on toys, but electronics. Dan took a look at conventional printing; there are 20,000 pressrooms worldwide, so the capacity is there. They know all about pre-press and plate-making, too, whereas semiconductor companies lack printing knowledge, so there are strengths and weaknesses of being a new company here, the first to learn the design rules, closest to market opportunity, albeit furthest from existing markets.

Steve Jones is someone who knows all about printed circuits, and has now changed his spots ever so slightly to run a company aptly called Printed Electronics Ltd

Steve looked back to 2000, a year of reckoning; 50 per cent of PCB manufacturing capacity was lost in the UK; there was huge contraction in the USA, with most of the business moving to China and the Far East. The volumes have been lost to us; and we can't compete on price. They can produce quality as good as us so for any volume item, it will not be in Europe or the USA.

What is electronics? This is interconnecting a bunch of components. Printed electronics is circuitry created with conductive and/ or electro active inks using a wide range of printing techniques. Of these, inkjet printing is the most exciting, one can move from design to production within hours. It does not work on nano-scale, of course, but it is capable of producing semi-finished products upon which silicon can be placed for more sophisticated applications. Low to modest up-front costs, a small footprint of machinery and cost of ownership is relatively small. Ink jet grey scale heads, inks and data management makes micron-scale printing possible. He likes robustly engineering processes that work routinely, so where are we now? Slightly better than nowhere, thought Steve. Commercially available precision industrially engineered inkjet machines do not exist. The palette of inks that represent a range of electronic components are only now being formulated. There is little understanding of repeatability, reliability or long-term functionality, and there is little understanding of how the materials will behave during multiple processing operations.

But inkjet has the potential – it is 10 × faster, 10 × more capable, 10 × less cost to manufacture; challenges include SMT and reliability, but the demands being placed upon inkjet – high precision placement, high resolution, high throughput, consistency and cost effectiveness – are largely being met, with the advent of the.

Granite base, Xaar grey scale heads and HSS ink jet heads, which now offer repeatability and accuracy. His own company is working on the concept of array heads, reel-to-reel working, and single-pass offering high-resolution images, so listen to Steve again in 18 months time. Or less.

Intel Capital & Strategic Venturing was represented by Abdul Guefor who explained Intel's interest in printed electronics. Their policy is to invest in companies of strategic importance. They are the largest VC in the world, with $255 m invested, but in very diverse activities, of which 60 per cent lie outside the USA. The plan to have a strong presence in emerging markets, and their focus areas include – mobile internet; digital home, enterprise; manufacturing and emerging technologies which include nanotech materials, biotechnology, advanced patterning. Intel is a platform company, and believes that printed electronics could complement many platforms; in the longer term printed electronics could disrupt silicon application issues. So a foot in both camps, then! He concluded that printed electronics is as exciting now as silicon was 25 years ago.

Dr Hermann Hauser is a director at Amadeus Capital Partners Ltd and said that there had been a paradigm shift in R&D, whereas the old telecom companies such as AT&T, Bell Labs used to do their own, now it is companies like Cisco, who have no central R&D, who are now moving to start-up companies. His company provides venture capital in the EU and UK, and looked for innovation partners, however Europe has 3/4 the number of start-up companies that the USA has, but only a third the amount of money. In the UK there is virtually no corporate venture capital in ICT, it is better in biotech where drug companies are more active. But Europe has always had good technology, it has access to global management talent, it has global market access, and has VC syndicates with firepower. There is positive Government support, and there are various DTI initiatives; also CGT is now lower (10 per cent).

Cambridge is not just a city, it is a high-tech cluster of companies, and such is their worth that Cambridge is in the top five globally, and is the No. 1 high-tech cluster in Europe. It is known as the “Plastic Valley”. There are 72 Nobel Laureates in Cambridge, and the Cavendish Laboratory has seen the development of DNA, LEDs, plastic logic, etc. Interesting to learn that there are 1,000 high tech companies in Cambridge, with some 40,000 people employed, and for them there is good VC support, with some great consultancies.

Jie Zhang is a Principal Staff Engineer at Motorola. She looked at challenges and opportunities in printed microelectronics. Printed electronics will compliment silicon, she thought, where cost is the main driver; printing technologies include screen, stencil, flexo, gravure, inkjet, and dispensing. (Ink jet). PET is the new TLA – printed electronics technologies, which includes transistor structures that are printable, and how lab-scale printing in- house led to sheet-fed printing, and then to web-fed printing reel-to-reel at Motorola. Printing resolution is critical for device performance, and also for dielectric properties and printed thickness. They have produced all- printed functional logic circuits at Motorola, and say that whilst the system has many attributes, such as throughput and quality, they have taken into account some general assumptions, covering throughput, labour cost per operator, hours worked, material costs, process equipment, and production costs. They have concluded that for printed electronic technologies, 87 per cent is material cost, labour is 2 per cent, and equipment 10 per cent and 1 per cent covers factory costs. International awareness and education in PET is available from INEMI and IEEE. Her conclusion – printed materials are everywhere, as platforms but what electronics can be embedded? Logic, communication and intelligence can be, and she stated that printable inorganic semiconductors will be produced, not organic.

Dr Thomas Lindner is the R&D manager at Hewlett-Packard, Corvallis, Oregon. They have four printing technologies under one roof: thermal ink jet, laser jet, liquid electrophotography, and piezo drop on demand. A development site, Corvallis produced back in1977 a combined wristwatch and calculator, then the HP12C calculator in the '80 s, then in 1984 came inkjet printing, they added digital projectors, and HP light scribe used for CD labelling. They introduced scalable print technology in the autumn of 2005, whereby you can produce 6 × 4 photos in 4 s. Dr Lindner presented a paper that looked at printing transistors; they have produced some competitive active devices, some novel precursor chemistries, and transparent transistors. They are also involved in a research project with Oregon Sate University on printed electronics.

Dr Vivek Subramanian hailed from the University of California, Berkeley to talk about advanced printed materials and devices for RFID applications. You can use Silicon – low frequency tags at 135 kHz – for animals, but they are too expensive for tracking items. The 900 MHz tag costs more than 10cents, but has good performance, and a range of several metres, but is not good in the presence of metals, and it hates liquids – so what about 13.56 MHz? Silicon RFID tags cost less than 7cents today, with chip attach it costs less than 4cents, and a strap attach for 13.56 MHz would be some 5cents. How to reduce this cost? The Holy Grail is possibly a reel-to-reel system, with a print system with a printed spiral coil. You can use electroplated copper which is good for distances of 10m, but not further. But by using nanoparticles, shrink their size down to below 10 μ when they become stable and conductive, you can then print the particles, which fuse together to maker a conductive path, and then print an initial seed layer for electroplating.

Wolfgang Mildner is the Managing Director at PolyIC GmbH & Co KG in Germany. They are chip printers. They want to make printed electronics which are thin and flexible, inexpensive and simple, pervasive and disposable. There are many areas of application: Auto identification, for one, displays for another and “smart” objects and devices. RFID is already in place, and in use, many of the retailers and logistics people are using it. Barcodes are being replaced by RFID tags. He mentioned the “smart” fridge that tells you what is passed its sell by date and which even orders a replacement! Big companies are following this vision – but when? Cost is the key, functionality is not; you can add functionality, but with a tag down to a few cents, then the market rises.

Displays – flexible, simple, inexpensive. Printed electronics has to be mass produced to be effective as a low cost item. Is it a threat to silicon? Yes. What are the innovations needed? Materials – select and optimise materials that can be printed – such as organic semiconductors, substrate as insulator or conductor. Technology – adapt technology to build transistor and other basic elements, design chips, etc.

At Poly Ic they now have an 8-bit RFID tag which operates at 13.56 MHz with a 7.5 cm reading distance. But they have not yet reached the limits. It's all about collaboration; they have joined with Siemens, and Kurz in a JV, where Kurz do large reel to reel printing, using Siemens know-how in electronics systems. They are also members of the Organic Electronics Association (OEA) of whose members are all dedicated specialists in the field targets – 13.56 high frequency; application fields for polymer RFID could include brand protection, security, ticketing, track and trace. Electronic products codes will come later. A very informative paper, given with great knowledge.

Dr Jukka Hast is the Senior Research Scientist at VTT Technical Research Centre of Finland roll-to-roll fabricated integrated modules. VTT have a 225million Euro turnover, employ 2,720 people and have been active in printable electronics and optics for some time. They see the benefits of printing as:

• high speed fabrication, high volume products at low cost of manufacturing;

• a low temperature process, so you can use flexible substrates;

• additive methods reduce waste in manufacture; and

• printing is an established technology.

Their objectives are to investigate the possibilities to fabricate active and passive electrical and optical electrical elements using roll-to-roll processes. They have a 100mpm printing machine with UV curing in place. Alignment accuracy is a critical issue – also integration of effective power sources into the products; how good are the transistors we can manufacture using R2R? (Reel-to-Reel).

OLEDS – all layers can be printed onto flexible substrate. Organic solar cells can be printed onto flexible substrates, and there is a huge potential in optoelectrical objects, but still many questions on material development. The new machine at VTT has changeable heads, and this includes direct gravure, reverse gravure, rotary screen, and flexo. They are undertaking a massive task here, happily with a strong international team of partners, and the results will be all very interesting in due course.

Dr Per Bröms is an applications specialist at Thin Film Electronics AB, who were founded in 1997. His company developed read-only memories, and thin-film memory circuits, and hybrid memories, and are now moving towards printed electronics.

He described their low temperature soluble digital memory system, which can be used for printing, it can be integrated with other electronic functions, is non-toxic, and very well protected on patents. The Memory Cell is robust, it can withstand many read and write functions, has an active memory film, and all convent ional printing technologies have been tried, satisfactorily. The market for printed memories, smart labels, smart packaging, printed RFID, low cost electronics (toys) is excellent, but security and anti-counterfeit applications are the best avenues to explore. As a unique ID, where memory cells can be rewritten many times; as secure ticket entry systems, where it is more secure and costs less than magnetic stripes. Rewriteable memory can be made extremely difficult to copy, such that forgeries are impossible (Plate 2).

Plate 2 Tabletop displays at printed electronics

Dr Christoph Brabec comes from Austria, from Konaraka R&D GmbH. Konaraka builds power plastic that converts light to energy – anywhere. The company develops and produces light- activated power plastic that is inexpensive, lightweight, flexible and versatile, which means that devices can have their own embedded sources of renewable power. Call them printed photovoltaics. By 2010 there will have been huge growth, some 40 per cent CAGR in photovoltaics. OPV (organic photovoltaics) are a real possibility, produced by a reel-to-reel manufacturing process on environmentally acceptable materials, with an energy payback time that is good, and combined with the low cost of manufacture allows the design of products with short lifetimes. For this there is huge demand.

Also from Austria was Klaus Schroeter, the CEO at Nanoident Technologies AG. He talked about the advantages of organic semiconductors. New materials are printable, and printing gives us unique technical features, we can get large detector areas, above 30 cm, using inkjet printing systems, on 50 cm large substrates. They can produce flexible photodetetectors, which can detect OLED light source; this is a new class of sensors, with integrated OLED elimination. Materials are non-toxic, disposable devices, some interest in high volume applications. His company is also involved with photodiodes/lines and arrays; sensor embedded OLED object illumination; sensor embedded electronic circuits. Their photonic sensor platform consists of photodiodes, in layers, glass or plastic substrates, optical transparent electrodes, all with ink jet printers, the minimum size is 50 ×50 μm. They are about to realise a transition from R&D to production, and are developing the processes, producing the devices in high volumes, beginning with CAC design, then inkjet printing, laser dicing, automated assembly, and automated test. Their inorganic fab manufacture, is large, (100,000sq.m) and has cost Euros 10 million.

Production time is dramatically lower, with only a few production steps. End uses include dust sensors, large area sensors for the PCB industry, (but here they are working with a test company, as no mechanical testing is done, it is done with an optical multiplexer, 50 × 57 cm) as readers for a biochip, as point of care in the medical world.

Professor Krishna Persaud came from the School of Chemical Engineering and Analytical Science at the University of Manchester, and talked about the use of conducting polymer materials for chemical sensing. Their objective was to simplify the manufacture of the sensor array and to improve robustness. They have used Kapton sheets, and various electrode arrangements have been designed and manufactured on this material to good effect, in smoke detectors, for example.

Dr Martin Krebs is the cheerful face of Varta Microbattery GmbH, Germany.

Varta make portable batteries, and Martin talked about flat batteries, microbatteries, where an electrochemical reaction of hydrogen with hydrogen ion yields a simple proton. These button cells are highly reliable, can be low drain or high drain, thickness is about 2.15 mm, and they can be surface mounted. They have some new lithium batteries, 0.4 mm thick, 0.3 volts, for smart cards, which are mass produced. Also small button cells, 6.8 mm thick, now working on a 3 mm, with a diameter of 1.2 mm. They have a lithium ion flex battery, called PoLiFlex, 0.5 mm thick in series, installed in cavities of devices. The next step is the direct printing of batteries, the advantages being mass production, by reel-to-reel printing, but they are low density, low rate capability. Future developments include dry cell carbon dioxide. There is a lot to do!

Geva Barash from Parelec in New Jersey came on next to talk about printed RFID antenna. His is a conductive inks company, formulating inks for heaters, defrosters, etc. and they have inks ideally suited for RFID. In this area his inks meet the demands for price, quality, repeatability; they can be printed flat screen, rotary screen, and gravure. Screen has big advantages when it comes to film weight control and definition. Their Parmod inks are also used in HF tags, 13.56 MHz, and in RFID library cards, at a unit $0.005 cost! Parelec are part of a certified printer programme, which involves printers, machine manufacturers, integrators, substrate manufacturers, they can produce prototypes and then go into mass production.

Elumin8 is an inventive and creative UK company run by Richard Kirk, who described how they used printed electronics in indoor and outdoor advertising media. He described how printed electronics could be used for lighting systems for airstrips, large animated posters, but electroluminescence is needed to raise the profile of the technology. It can be used in architecture, and gives a client an unusual marketing approach. They sponsor design students, and use EL in TV advertising; they are working with 6 motor manufacturers on EL. Large format they have made their own. The Wine Tower at the Stansted Radisson hotel was shown, also we had a glimpse of the designs his company is working on for Terminal 5 at Heathrow Airport where complete walls, 3-4 m high and 14 m across will contain EL displays from Elumin8.

Edward Voncken is the CEO of Orgatronics b.v. in The Netherlands. They manufacture OLEDs by inkjet printing. Organic electronics combine functionality, and make OLEDS affordable. OLEDs are extremely simple devices; build up of layers, using a glass substrate. OLEDs have good video properties, offer freedom in design, are energy efficient, are recyclable, potentially low cost, and have combined functionality. Issues include performance lifetime, development costs versus volume, the substrates are important - availability, quality and costs; also manufacturing costs, as there is no “killer” application yet. Why inkjet? It is a non contact process, operating at low temperatures, you can place material where you want it, and it is material efficient; you get high flexibility in deposition area, size and shape. They use a combination of inks, heads, design, substrate, and drying; these are all factors in the picture. They do vertical printing with UV curing. No masks, needed of course. The equipment is roll to roll, so it needs very high volumes, as there is continuous processing. It has potentially lower costs, naturally. They have a machine with its own clean room, it requires little or no manual operation, and it's a fully integrated line, almost fully automatic. They offer R&D and process demonstration, and students are being retained in the design and application concepts for OLEDs, working on demonstrators for game boards, low costs lighting and signage.

Basically, OLED inkjet printing works well.

Dr Jonathan Halls popped across from Cambridge Display Technology. He wanted to share with us his experiences of working on P-OLEDS – polymer light emitting diodes. CDT was founded in 1992, as a spin-off from the famous Cavendish Laboratory. A polymer-OLED is extremely simple, a simple lay-up, operating at low voltage. They have a wide variety of applications, as a display technology they offer, flexibility, low power consumption, high contrast, and a wide viewing angle. CDT is driving commercialisation, which hinges around lifetime; the major limitation is the blue lifetime, but CDT have significantly improved lifetime and efficiency, such that 200,000 h with blue lifetime is possible, and all other colours have increased, too. The production of polymer dendrimer hybrids was the result of a JV with Sumitomo Chemicals, they now develop and sell such materials into the display market, and now claim a lifetime of 800,000 h lifetime now. Phosphorescent red is now the leader technically against fluorescent red. New lifetimes means many possibilities, portable DVD players, camera screens, in the future the large screen TV itself.

CDT's main focus is on inkjet printing, the key to efficient and scalable manufacture, as you can put material where you want it. They have a machine with 128 nozzles on the Spectra inkjet heads. Drop place accuracy is vital, with 5 μ accuracy possible. They bought Litrex in the States as a machinery manufacturer, their Gen 2 printer is a very accurate machine, so they can move to larger and larger glass sizes, as the machine is very heavy and thus very stable. The Gen 7 is a 2 × 2 m machine, with a large number of heads, and thus short print times. Concerning pixel size, they have gone from 200 ppi down to 90 ppi, and ink drop size has moved down to 16 um from 39 um; the Xaar 2Pico litre drop size is boosting accuracy. CDT have a 14” wide PLED display screen, Ink jet printing is a direct write process, therefore suitable for flexible substrates, Toppan have done some extremely nice work using roller printing, screen printing from Add- Vision looks very good too, they can pattern and etch the ITO.

The market drivers are portable multi-media devices, and large screen TVs; larger glass sizes have driven down the price, the Gen 7 at 2 m might be the optimum size. For displays P-OLEDS will be the most cost-effective, with a reduced bill of material costs, and by 2,008 the market for PLEDS and OLEDs will stand at $5.3 billion, a CAGR of 84 per cent from now!

Putting forward the view of a user of all this printed electronics was Katherine Williams from the John Lewis Partnership. Founded in 928 by John Lewis, this is an unusual company, he handed the company over to his employees in 1928, and they now run as a profit sharing organisation; last year £120 million was handed back to the employees, the equivalent of 8 weeks pay. They are the largest privately owned company in the UK; hey have 27 department stores, with 172 Waitrose shops in the UK and five more to be opened, and ten new department stores in the next ten years. Turnover is £5.8 billion, on which they make a profit of 10 per cent.

They use a lot of labels. Mainly black, but with increasing use of colour; it is still a manual process to change labels, so they undertook an electronic shelf edge labelling trial of E-labels, controlled through a laptop and wireless. They installed it on their camera island at John Lewis in Oxford Street. Cameras are displayed in glass cabinets, so it is cumbersome to change labels manually, so they tried labels using E-cells for 5 months. The installation went well, but they found that the customer's view of the label depended on angle, and lighting, it was better under fluorescent lighting, and other considerations were battery life, they sometimes lost pixel quality, and the red colour was not sharp. Their conclusions were that the devices too expensive at the moment. Devices need to be more robust. Battery and pixel issues need to be resolved, and strong colours are required. They need to be smaller, and thinner, and more compatible in department store environment.

The global picture shows that 2,500 stores worldwide will change over to electronic signage. In Japan over the next two years all department stores will be using e-signs, against only four in the UK. Given that there can be 50-100 price changes per day; the demand for such a device is enormous. Once a proven system becomes available it will grow rapidly.

NTERA in Ireland sent over their MD David Carr who told us about Visual DNA, or reflective displays. They operate on a warm white or translucent background. They have superior readability, longer battery life, offer arresting visual communications and have great application in consumer electronics such as digital still cameras. Further applications are in displays, optics, interfaces, the big target is the mobile device, as a multifunctional tool. They can offer 85 per cent transparency where needed. The printable electronic layers or electrochromes can be deposited via dipping or inkjet printing, controlling opacity or transparency. Such displays are being integrated into white goods, and the future work includes the development of natural colours, for various device architectures.

Andy Bateman is the Business Development Director at CENAMPS in the UK. Cenamps is acronym for the Centre of Excellence for Nanotechnology, Micro and Photonic Systems, promoting emerging technologies in the North- East of England, and incorporating the talents of Newcastle, Durham and Teeside Universities. Work focuses on nanotechnology, biotechnology; they have a small team of 18 people operating under the European 6th Framework Programme, mentoring north east companies towards network investments in businesses ranging from lab stage to production stage. They are interested in developing facilities of their own, especially in the thin-film area, calling it the Centre for Emerging Nanotechnologies.

Nanotechnology is having a huge impact on industry in the chemicals and materials sector, and the ICT sector. Plastic electronics can be seen riding the bow-wave of the nanotechnology roadmap, with the emerging markets moving towards flexible functional materials by design. This involves substrates, inks, coatings, and additive and subtractive chemistries, which is where the PETC comes in, the Plastics Electronics Technology Centre. This is a. 30,000sq. foot clean room, with dedicated labs and offices, and pilot lines. The centre will respond to market needs, the market is strengthening all the time. Early applications include passive logics, backplanes, alternative direct write technologies, etc.

Dr Colin March of The Technology Partnership. They specialise in products and processes for large companies and are active in printing. Here there are two technologies – non-contact technologies and drop on demand systems. In this field TTP makes pieces of kit that in turn make things. Essentially they are electrical and mechanical engineers, who have developed printing techniques based on digital application. The brief was for a single pass system, operating at high speed (one metre per second) which would print on to non- absorbing surfaces, onto film, glass and plastics, and which should be able to put down a huge range of materials. As a result very precise ink jet printing techniques were developed, with excellent edge definition, and excellent line placement. They can also do 3D printing, can offer PCB resist application. TTP are specialists who see the larger picture.

Conductive Inkjet Technology sent along Mike Johnson to talk about inkjet metallisation technology. He said it's a new process – a solid inkjet system, an additive process, using standard digital inkjet printing, but now with a prior processing beforehand to pit down a seed layer for plating with copper as an additive process. It can be used in all manner of applications. A UV curable non-conductive ink for piezo-electric jet has a dual role; it provides adhesion to the substrate, and provides an image. Resolution is now at the 50 μ line width barrier, but the system operates at 100 mu; now which is fine. They are working with Preco and are using their expertise is in web-handling, on a system running at 30 m/min. Uniform film thickness with a smooth top layer surface is being achieved on their prototype machine which is up and running, providing a PET of 50-200 μ thick, with 100 um lines and gaps, and at a cost of one US cent for 10 sq.cm.

John Corrall works for Konica Minolta and looks after inkjet in Europe, and the requirements for industrial inkjet heads. John looked at a variety of permutations for inkjet machines when used for various applications – nanotechnology demands, display manufacture; print heads can be thought of in terms of chemistry and resolution, where you need small drops for high resolution, or where, in the case of PCBs, you need a good quality UV ink head. In a detailed paper he looked at the requirements of the ink jet heads related to application. Very thorough and informative.

Dr Arved Huebler works for Printed Systems GmbH in Germany, a spin-off of Chemnitz Technical University Institute for Print and Media Technology – they claim to be the first fab for mass printed electronics. Printed Systems – start-up company. Electronics are everywhere: things that think, smart objects, ubiquitous computing. There is an interface between low end and high end electronics, and his company brings the two together. The combination of polymer electronics and mass printing brings low-cost electronics to all areas of life, there is no competition to the high end (silicon), the USP of printed electronics is that they are flexible, very cheap, can be thrown away, and suit a mass production design. Talking cornflakes packets might be an example! (one dreads to think). Mass produced integrated circuits are now available produced by a combination of offset, gravure and flexographic printing, using a non-conducting layer (F8T2) and a conducting layer (PD0T) with an isolator of their own development., Resolution is 100 μ, they operate at 1 Hz at 48 V, 4 Hz at 80 V. Merging the fields of materials, electronics and industrial production processes brings Printed Systems into the right place at the right time.

Dr Reuben Rieke is the President and CEO of Rieke Metals Inc. in the USA, and he had flown over to tell us about his range of highly reactive metals which can be used to manufacture novel organometallic reagents. These reagents can be used in the synthesis of unique polymers and well as fine organic chemicals. They manufacture 3-alkyl polythiophenes, polymers which are highly soluble in organic solvents. Thus, conductive inks come into view here, and applications for his materials include plastic electronics, RFID tags, OLEDs, photovoltaics, at dramatically lower prices.

Dror Mualem of Pixdro, another American visitor, was proud of his company's achievements in the field of industrial inkjet printing. They design, develop, integrate and manufacture inkjet technologies and processes for a variety of applications, and working with the OTB Group in The Netherlands offer complete systems for organic electronics applications, they have a massive and fast inkjet press (1.26 sq.m/s at 600 dpi resolution), as well as the Lab 160 laboratory inkjet system for materials development. Further down the line is the IndP350 high precision industrial inkjet press for PET applications. Their OLED printing g system is now a complete production line. They say that their inkjet system allows for the visualisation of the nozzle functionality, as well as droplet shape, speed, direction and volume, and uses alignment cameras for measurement of the substrate (via fiducials) to the position of the XY platform.

Dr Karel Vanheusden is from Cabot in the USA, who has a complete print laboratory for industrial inkjet printing and processing. The inkjet printing of what they call e-materials allows for the creation of solar panels, fuel cells and batteries, electronic components such as capacitors and resistors, PCB (rigid and flex) As well as SiP, flat panel displays and flexible displays, and RFID and disposable electronics. Inkjet Ag nano-paricle ink is now available commercially, and thus PCBs can be produced far more simply and cheaply. And the ink itself can be applied by gravure as well for flexible substrates. Future developments include inkjet nickel as well as silver, with the choice of resistively where required.

Freak Paso is the Product Manager at Veto Instruments in France. His company provides nanoscale and microscale measurement equipment, including atomic force microscopes, scanning probe microscopes, and stylus and optical profilers. Their process equipment tools help creates nanoscale devices, and include ion beam etch and deposition, physical vapour deposition molecular beam epitaxy, metal organic vapour deposition and precision dicing and lapping technologies. Printed electronics are using the Wyko Rollscope portable white light interferometer for measurement on roll to roll printing and on offset plates. Surface metrology, it is called and it is critical for the quality control during the printing of RFID, OLED, batteries, and biosensors.

Summary

A very well-planned and managed conference, which was wonderfully oversubscribed, and has been likened in excitement to the halcyon days when the wonders of the PCB were being illustrated, and when people made a great deal of money by putting words into action. Here is another huge market that belongs in no category other than it's own, and printed electronics are now with us in a rapidly changing form and application for many years to come.

John LingAssociate Editor, Soldering & Surface Mount Technology