Plastic Electronics emerging from the labs =
near term inkjet openings, long term boom

Looking at plastic electronics, there are some things we know. We know it will be big. More than just another new technology, rather a revolution in terms of expansion of our ever-growing electronics-based world. We know there is intense interest and loads of pertinent research being pursued in academia by a number of company R&D labs. And we know inkjet and perhaps other digital printing technologies will play an important role.

There's more we don't know. We don't know when the technologies will become commercial on a large scale. We don't know how large a role digital will play, although from what we know now, we've made some tentative projections. In short, we can't afford not to watch it closely and participate as opportunities open up.

These knowns and unknowns are what drew our Liz Ziepniewski and Mark Hanley to this year's major Plastic Electronics conference earlier this month at Messe Frankfurt. The trip in large part was to look and listen, but also to raise the visibility of digital technologies. To this end we signed on as a co-sponsor, Liz addressed the Organic Based Flexible Displays break-out, Mark was on a panel entitled "Vision 2010: Technology and Business Road Mapping for Plastic Electronics," and our Global Industry Review report on plastic electronics was distributed to attendees.

I.T. Strategies produced a summary report after returning from this conference. This report was one of the many Market Applications reports distributed to clients of I.T. Strategies. So now, for some informal and more spontaneous post-conference perspectives on this revolution in the making and the potential for digital printing, we meet with Marco Boer and Mark Hanley, the latter fresh back from the event.

First, we talk definitions.

As with any emerging field, definitions are in flux and still a bit murky. This language lag can be confusing, and could be the topic for an entire report. All the adjectives used to describe this field seem a bit ambiguous. From our standpoint-seeing this field as a key that will take our technologies from printing to manufacturing-"printed" electronics works (as discussed in these pages last December). The industry, on the other hand, talks mostly about "flexible" or "plastic" electronics. Flexible not in the sense of suitablility for diverse applications, but rather pliable. This is the sense, also, that "plastic" is used (the bulk of today's ICs are already on rigid plastic substrates). But within this simmering world of research plastic seems a leading modifier, so also a choice for this morning's session. But it's also noted these programs have loose edges, spilling over into broad fields such as nanotechnologies and nanostructured materials, photonics, and organic electronics.

Next, why is it so interesting? "One reason," Mark says, "is that it's the electronics industry, not the printing industry, that is driving this. It is the electronics industry that is hungry for this, for products that are thin, flexible, and cheap. It's a long term shift in the electronics field destined to take us from expensive and rigid to inexpensive, flexible, and large area. It's extending the capabilities of electronics. It's moving us toward throwaway electronics."

Envisioning
Examples help. One is flexible display screens, screens you can roll out, and screens that can cover a large area. It is electronically functional surfaces such as moving or non-moving display, or planar lighting that could be spread over large areas, as panels on walls or ceilings. There could also be sensors to detect pathogens or poison gas, or advanced and much more affordable photovoltaics to generate electricity from light. There are auto sunroofs that can be changed from clear to dark blue, but these are expensive today.

Mark works to cut through complexity and get down to the basics. "Look, essentially, with plastic electronics you're taking the pre-existent paradigm of "printing" and you're saying Hey, this is a manufacturing technology. Why? Because today's semiconductors, today's ICs (integrated circuits), are basically a piece of material that functions essentially like an almost infinitely variable switch. That's what the silicon in an IC does.

"Unfortunately silicon is a solid material that needs to be manufactured normally in a subtractive process that is complex and expensive. Now, imagine you are no longer dealing with solids, but with liquids, liquids with significant functional similarity to silicon. It was back 25-30 years ago that researchers discovered liquids that actually had semiconductor characteristics, liquids now termed organic polymers. By putting down differentiated layers of these materials you can emulate the capabilities of silicon. Liquid technology can be used to manufacture FETs, field effect transistors. If you can do that, you can print it. And you can print it on flexible substrates, roll to roll, a manufacturing process that might cost almost nothing compared with today's semiconductor manufacturing technologies."

We envision an inexpensive, roll-out display screen the size of our conference room white board linked to a wireless PC. The back side of the screen would have printed field effect transistors, and the front printed organic light-emitting diodes. Aside from the capability to physically scroll out the screen, the cost today would be prohibitive. With printed electronics, it could be easily affordable.

From Research to Commercialization
It's been many years since the electronic potential of organic polymers was discovered, so why all the interest today? The reason, basically, is that it has taken that long for us to break out of material research in the labs to an early stage of commercialization. Development has been moving out from university researchers to major chemistry companies around the world.

Most of this work has been in academia, and still is. Around a third of the attendees at the Frankfurt conference were from various universities around the world. But there were also presentations from chemical companies including Merck Chemicals UK, DuPont, Honeywell Specialty Chemicals GmbH, and Akzo Nobel Chemicals.

Marco wonders if this breakthrough has the potential to bring greater influence in electronics to the Western world. A good portion of the R&D in Printed Electronics has tended to be in central Europe, in Germany, The Netherlands and Austria. Of course there's a lot of interest in the Far East as well. Epson, a leader in small flat panel display, is also an inkjet leader. At the Frankfurt conference there were two speakers from Dai Nippon Printing. The stakes are incredibly high, but Mark advises caution since application of this research has barely begun to be tested.

Remember, even if it all works, the functionality of printed electronics remains way below that of today's silicon. Speed, for example, is one of the really big, basic stumbling blocks. Yes, in a PC speed is critical, but not in some display screen applications. So no one is suggesting the new printed electronics will replace the old silicon crystalline electronics. What it will do is create new markets. Theoretically, in a work environment, you could have electronic controls or switches built into the sleeve of your jacket. Things we can barely imagine today.

Printing
Today for printed circuits, rigid or flexible, we're now looking at three broad manufacturing choices.

First there's true analog printing, essentially any analog printing including screen printing which has been used for printed circuits for decades. Hence the term "printed circuits." In fact this form of screen printing differs quite a bit from conventional screen or other analog technologies and is only a sub-process in today's electronics market, but does lend credibility to printing as an entry point into this new market.

Today's dominant manufacturing technologies are termed "hybrid analog gas, solid and liquid deposition technologies." These include etching, vacuum deposition, epitaxy, electrolysis, electroless plating, and metal reduction among others. For today's mainstream applications, these are expected to coexist with tomorrow's generation of plastic electronics. However, as mostly subtractive processes under highly specialized ambient conditions (vacuum, heat, etc.) they are wasteful and very costly compared with true printing which as an additive process is more environmentally friendly.

Direct digital printing, mainly inkjet, is seen as the ultimate ideal. It offers a number of advantages. There will be metallic inks and more importantly, organic polymer inks. As a non-contact technology, it will open up a whole new world of electronic circuit media. For the microprecision-oriented electronics industry, inkjet can now be directly controllable down to the level of the picoliter droplet. And there are all the other demonstrated digital printing strengths that have been proven in graphics applications. These include easy integration into the digital data flow, infinite run length variability, and compact modular hardware for inline printing in a manufacturing setting.

If inkjet proves its ability to scale up in the future it will become the preferred technology, the core enabling technology for a variety of new markets. On the other hand, today most people involved in the plastic printing scene tend to assume for volume applications analog will dominate-gravure, flexo, or whatever. "Inkjet is the ideal, but it's a lot further off," Mark concludes. "So it's interesting to see us working on a market which for now promotes analog printing."

It is expected that digital will move into this industry in phases. First will come applications such as lighting and monochrome, static informational flexible display screens. But full-color moving, scrollable large-area screens? Not for at least five years, Mark believes. Same for true field effect transistors, switching components that drive sophisticated electronic devices. "This thing has been smoldering for 25 years," Mark opines. "Now the first flames are beginning to appear."

Barriers
"Sounds to me if you're playing with organic chemistries, the viscosity of these substances will be pretty high. Is that something inkjet can jet?" Marco wonders. "Will this require fundamental changes in inkjet technologies?"

This depends on the application, among other things. In the materials area the ultimate goal is semiconductors. But there's also a market for simple conductive chemistry.So there's a lot of work going on today using inkjettable silver-based inks. Silver is interesting because it can be reduced to nano-sized particles. It's also interesting because most conductive metals (whether you print or etch them) form an oxide, and oxides are generally not conductive. But with silver, the oxide is just as conductive as the virgin metal. The down side of silver is that it is a heavy metal, which means it's toxic, and also of course expensive.

So there's strong motivation to get beyond silver, to polymers, organic polymers, even though they tend to be viscous and their conductivity performance is weak. Sensitivity of these materials to heat is another quality that appears to limit the process to piezo rather than thermal inkjet.

But the non-contact nature of inkjet may more than offset such limitations. Field effect transistors are manufactured with a layering process. Normal analog graphic arts technologies are by nature two dimensional. Getting up to the fourth or fifth level looks like building a third dimension, and here offset may be unsuitable.

Indeed, reports at the Frankfurt conference did include tales of problems in pilot programs using analog technologies, problems with registration and materials incompatibilities. We're reminded that with any process, there will be pros and cons, that there are no final answers. Materials research has come a long way, and now people need to work more on research in printing processes.

Marco sees another another barrier: money. "So who has the money to invest on the printing side? Will it be the Hitachis and the Intels of the world? Are they saying, 'Wow! This is the next step for us!'? Is it the press manufacturers? Is it the 3Ms, the DuPonts, the Kodaks?"

We're not that far along yet, Mark responds. "What everybody has done so far is develop materials in the labs. Hardly anyone has gotten into the manufacturing yet. Materials research has taken the longest and has been the most critical thing technically. But economically, the whole thing doesn't fly unless you can manufacture it cheaply. So the real vector of change will be the manufacturing technology, namely the printing. The truth is we don't have much experience with this yet."

Today's Targets
Marco wants to get specific. "It all sounds good and interesting, but what's the bottom line for our vendors today, for the inkjet head manufacturers, for example? Should they target all the academics that are trying to figure out how to jet silver? How do they participate?

At this stage, we decide, it's giving them small, affordable experimental equipment, the Dimatix approach.

The chemical companies have more R&D resources, and they need to be looking at inkjet today, even though it may be further off than other deposition technologies. Nobody is really on the same page with all this. It's time to go talk with individual companies and find out what their angle is on this. "In England I've seen large electro-luminescent display panels already operating in store windows and elsewhere," Mark notes. "Is that suitable for inkjet? We don't know yet. But it might certainly pay off to find out. I feel strongly there isn't a single printed or plastic electronics market. There are markets."

Marco reminds us markets are appearing that we might not have imagined a few years ago, for example food printing. There's now a mini-industry printing cookies, for example, with HP inkjet food dyes, that this has reportedly grown into a good decentralized business. Food printing traditionally has been a laborious craft operation, but with high demand, it had to be scaled up and inkjet turned out to be the answer. "It sort of grew organically; we never could have projected that. Now, with this new technology, envision greeting cards that glow when you open them up!"

"Well, they're just novelty markets," Mark responds. "The kind that may or may not be there in another five years. Let's think of markets outside what I see as our surplus economy. Other markets are a lot more fundamental. For instance, if you can create flexible photovoltaics you can go to Africa and supply them at a cost they can afford to drive water pumps in desert countries that literally save lives." Vast disparities in demand around the world, most yet untapped, all represent potential markets barely envisioned currently.

We wonder, for example, how ever cheaper, disposable electronics might impact the environment. Marco notes there will certainly be environmental trade-offs. On the down side, there's more burden on the landfills. On the up side, there's the potential for much more cost-effective energy generation from solar cell arrays. Controllable thermal characteristics and tints of windows that can conserve heat.

Inkjet as a Complement to Analog
Turning to the status of inkjet technology in all this, we conclude there are opportunities today, even though the new industries are in a prototyping phase. High volume and low cost doesn't sound like a fit for digital printing. But even at this stage digital can complement the many other technologies being explored, nanolithography, physical and chemical vapor deposition, thin film silicon, organic conductive polymers, and all the rest for both precision pattern and area layering applications.

There's a lot of trial and error in this unfolding field. A number of companies are moving toward commercialization according to various reports. Hewlett-Packard is working to print circuits with its thermal technology. Philips in the Netherlands use Dimatix heads for printing OLED displays for cell phone screens according to an article published by IEEE last month. Motorola in Illinois has a project to develop electrically functional inks that can be printed on flexible substrates with standard graphic arts presses. A lab in Germany is said to be printing functional thin-film transistors from organic semiconductors with roll-to-roll equipment. None of these probes, however, have reached commercialization.

An early application that is showing promise is printing RFIDs. Here performance is conditioned by where the tag is placed, the kinds of materials, what frequencies are used in the system, and the size and shape of the antenna. Finding the optimum combination of these variables is difficult using today's production technologies for antennas. But experimental antenna trialing is a natural for inkjet right now and the potential is huge.

"This, to be sure, can be very lucrative for the right vendors. But it's typically what the market doesn't look at," Mark observes. "Because it's difficult, but that's exactly where inkjet can get a hold on RFID today. And as it grows up and becomes a volume flexible electronics application, through that credibility point inkjet may become a mainstream RFID technology. We're always looking forward, but forget about production. That's mostly the future. Inkjet may be exactly what you need right now."

Walk Before You Run
"So the business model of Dimatix looks like a home run at this stage of the market," suggests Marco. We agree that this company seems to be the one effectively pursuing these markets at this point. The former Spectra, Inc. now renamed, is positioning itself to lead inkjet into these developing industrial markets, to make the transition from being a printing technology to being a manufacturing technology.

The formal announcement was just last month by the Materials Deposition Division at Dimatix. The initial products are described as low cost solutions for high-precision jetting of fluids onto any type of surface. A groundbreaking feature is the "fill your own cartridge" concept. Combined with low cost of ownership, it's a tool that lets users experiment with processes and prototypes and move into low volume manufacturing of a range of flexible electronic products.

Unlike the ill-fated program of some vendors who scale up too fast, the Dimatix approach may work. Mark drives this home. "When people try to jump from printing to industrial they tend to want to do everything at once. So they come up with expensive, massive, untried and risky systems and that philosophy has not worked. It's failed again and again. It looks like the philosophy of Dimatix is to adapt to the reality that the market simply doesn't know what it wants or needs, and doesn't know what inkjet can do. So Dimatix says you don't need to know. You don't have to take a big risk. For, say thirty thousand dollars we'll give you a very small rig you can use experimentally with our support, software, a head that can handle almost any type of chemistry you want."

Lot's of people are watching this with great interest since it's a radical departure from the old business model. Mark sees it as a very creative, even daring thing. He believes it corresponds to many of the needs of the current markets. No, the model won't create a market worth tens of millions of dollars. But this could be a gateway into that. In short, Dimatix is taking the risk instead of the users. It's the appropriate technology in terms of scale and cost. It will allow the academic world and commercial R&D to take this forward.

Crossing the Comfort Barrier
One of the side effects of this is that if it works, it makes inkjet, by word of mouth, suddenly credible. Today, most people in this field are interested in inkjet today. But there are very few people who can say they feel comfortable. We expect this will cross that barrier.

Strangely enough, at the Frankfurt conference, among the more than 400 attendees inkjet vendors were pretty invisible. Dimatix gave a presentation and exhibited as a component supplier. There were people from a few analog printing companies, but only a couple. Among the other presenters were speakers from a number of familiar giants, among them DuPont, Honeywell, Nokia, and Philips.

One of the interesting things about this market is that there seems to be a huge gulf between all the talk, conferences, and research on the one hand, versus clear-cut strategies by potential vendors to get in on the ground floor and move with it. "It's a fundamental problem with this market," Marco notes. "There are so many different ways of looking at this, so many different conferences, how do you know you are hitting the right ones?"

"This fall alone, worldwide, there are maybe 15-20 conferences on this topic," Mark says. "That's too many. We're suffering from a surfeit of events and not adding much to people's knowledge at least not on a practical level. Three conferences are just as likely to increase your understanding as fifteen. Our advice is this: you don't need to go to all of these things. Pick judiciously. Since a large amount of materials research is being done in Europe-and not just the UK-it seems that's where you most likely can learn things. Here in the U.S. there does not yet seem to be the same level of activity, Dimatix notwithstanding. And it is the technical conferences that are likely to be most helpful, compared with digital printing conferences, where my sense is that there's generally not much new. So look to the high-powered scientists.

This is an area we need to be cautious about. There are a lot of small start-ups in these fields, but we need to be cautious about them. It's the people doing the relatively simple things that we should focus on. Things like greeting cards and electroluminescent chemistry that doesn't require a lot of circuitry. Monochrome digital displays rather than color ones. These are the kinds of applications most likely to be successfully commercialized at this point.

With this article, the main goal is to simply wave a green flag, to say the printed electronics race begins here, Mark concludes. "It's what began over twenty-five years ago and has grown ever since. It's come to the surface now and I don't think it's going to end in a bust. There will be happy people and disappointed people. It's too basic, it's too important, too much basic science invested, too many big companies involved: this one is not going away. Unlike, say, textile printing, this is a major departure in electronic science; it will change our electronic world in future decades, and digital printing will surely play a major role."