Applications-based assessment for the printable electronics market
07/01/2008
Printable electronics has been on an exponential growth curve for many years. Current prospects for printable electronics include sophisticated patterning to create memories and transistors; the variety of materials for printed electronics has also expanded. This article examines a number of technologies and applications for printed electronics that are gaining ground, in particular, e-paper, OLEDs, and photovoltaics.
 Revenue in printed electronics applications markets is expected to hit more than $30 billion in 2015. |
The focus for printable electronics is necessitated by the huge long-term potential that firms see in it (figure). These drivers, listed in Table 1, also define where the opportunities for printed electronics exist. According to several surveys by NanoMarkets, more than 80% of future revenues from printed electronics will fall into a relatively narrow group of applications areas. These comprise displays and signage (including backplanes), lighting, RFID, photovoltaics, and sensors. This article focuses on e-paper, OLEDs, and photovoltaics.
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There are three critical directions for the inks used in printed electronics: 1) the development of inks using organic materials, which promise the ability to print sophisticated electronic and optoelectronic devices; 2) the use of nanomaterials in inks, which provides a way to create higher-performance inks. Silver inks made from nanoparticles offer better conductivity and lower sintering temperatures; and 3) the arrival of printed silicon, which promises to bring to printed electronics the vast knowledge of processing silicon for electronics applications.
Printed displays and signage
There are five major actual and potential opportunities in the display industry. The least talked about is represented by color filters for LCD displays, which are now routinely printed. The other four areas are e-paper, high-end OLEDs, low-end OLEDs, and display backplanes.
E-paper: E-paper has emerged as something of a “poster boy” for printed electronics. This is primarily because E Ink, which dominates the e-paper segment at the present time, has a technology model based on an electrophoretic ink. E-paper is not a single technology, but rather a class of technology defined by its user characteristics, not by its underlying technology, so there is no implicit reason why e-paper should be printed. But the e-paper approach being pushed by E Ink shows no sign of losing its grip anytime soon. The other reason why printed electronics should look to e-paper as an area of opportunity is that the OTFT (organic thin film transistor) backplanes that are now used routinely with e-paper may be printed.
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NanoMarkets believes the biggest opportunity for printed electronics in the short term in the display sector will continue to be e-paper. We would not be surprised to see the market shift away from stand-alone book readers to rollable display add-ons; handheld devices dedicated to a single application have not done well in the recent past. In the end, signage rather than book readers may prove the nearest thing to a killer app that appears for e-paper. Electronic shelf labels (ESLs), in particular, seem extremely well-suited to e-paper’s capabilities. ESLs now use LCD technology, but the low-power consumption and ability to be read in sunlight that e-paper offers would be very attractive in this particular application.
Printed OLEDs: The prospects for printed OLEDs don’t look good in the short term, but there is one exception to that rule: the low-cost/low-performance OLEDs being advocated, especially by Add-Vision. If the cost of these OLEDs can be made very low using conventional screen printing, as Add-Vision believes they can, they would have immediate applications in backlighting and other consumer electronics applications.
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Four or five years from now, the printed OLED may be generating some real revenues. The arrival of small molecule inks may help in this regard. It is difficult to believe that OLEDs (printed and otherwise) will not ultimately make a breakthrough into the main display segment of the cell phone industry, especially if power consumption advantages can be proved. Many OLED manufacturers are making a strong push in that direction, and the vibrant color and other attractive features of OLEDs will certainly give OLEDs a good shot at this market with printing potentially playing a role in keeping down the costs of manufacturing.
OLEDs: Potentially, OLEDs bring a number of very attractive features to the lighting marketplace. (In the context of this report, we are talking not just about OLEDs, but also about printed OLEDs.) They don’t consume much power, can be fabricated on flexible substrates, and can serve as floodlights. (High-brightness LEDs [HB-LEDs] are more akin to a spotlight, so OLEDs are potentially complementary to HB-LEDs. At the same time, they can beat electroluminescent lighting [EL] at its own game.)
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In the future, it is possible to imagine OLEDs taking a significant slice of the general illumination, architectural lighting, and backlighting market. Backlighting is especially attractive as an initial market because OLEDs are much brighter than EL, and unlike the current compact fluorescent lighting (CFL) technology used to backlight many current LCD displays, no additional optics are required with OLEDs.
NanoMarkets believes OLED lighting is also an attractive opportunity from the supplier side because it is receiving substantial support from governments as an energy saving solution. European government money is being put into the OLA project, for example, and in the US, funding is coming from the US Department of Energy. Another reason why OLED suppliers are seeing opportunities in the lighting space is that it is an opportunity to sell relatively high value-added products without having to worry about active matrix backplanes, which have proved so tricky in the display space.
Printed photovoltaics
Thin-film photovoltaics (TF PVs) is a well-established industry and offers a number of advantages over conventional PVs (crystalline). These advantages include lower cost and lighter weight (making it easier to create viable rooftop panels). The disadvantage of TF PVs is that they typically have lower conversion efficiencies than conventional PV, although this varies depending on the actual thin film material being used. Until a couple of years ago, TF PV was dominated by amorphous silicon (a-Si), but both CdTe and CIGS are now significant factors. NanoMarkets has always included organic PVs along with TF PVs, but they have a somewhat different value proposition to other kinds of TF PVs: much lower conversion efficiencies, the ability to be used in dim sunlight (as a result of its tunability), and (potentially) lower costs.
Most TF PVs are created using deposition techniques; however, a few firms have begun to examine the possibility of printing PV. The poster child of printed PV is Nanosolar, which has developed a CIGS-based ink and has recently shipped its first solar panel. Nanosolar says it has developed techniques by which thin film CIGS can simply be printed to create an efficient solar cell with unprecedented yield, materials utilization, and throughput. Moreover, Nanosolar also says that printing solves an important chemistry issue for CIGS; simply by virtue of the particles being mixed in the right overall amounts, one can ensure the proper atomic ratios of the CIGS elements are guaranteed wherever the ink is printed, even across large areas. Nanosolar also claims the solar panels that result from its technology are lighter, cheaper, and as efficient as traditional solar panels. Another firm that is focusing on printing PV is Innovalight, which is using a silicon nanoparticle ink to create panels.
It will be interesting to see how other TF PV firms will bring printing into the mix. In addition to facilitating roll-to-roll (R2R) manufacturing, printing will better enable the creation of PV on flexible substrates, and this in turn will create opportunities for novel products such as smart curtains as well as lower-cost integrated building systems.
Conclusion
Printed electronics has come a long way since NanoMarkets first started covering the sector four years ago. At the time, there was little to show in terms of revenues, other than the fragmented revenues from thick-film electronics, which, even then, barely counted as printed electronics in the sense that most people want to use the term. As we move into the next decade, NanoMarkets expects to see printing increasingly become a key strategic tool and the major segments of the printed electronics markets–displays, lighting, RFID, PVs, and sensors–will begin to measure their revenues in billions of dollars. In Table 4, we provide our projections for the key segments of the printed electronics market.
Acknowledgment
This article is an abridged version of a NanoMarkets’ report, “Printable Electronics Market Outlook: An Applications-Based Assessment,” at www.nanomarkets.net.
Lawrence Gasman received advanced degrees from the London Business School and the London School of Economics. He also holds a mathematics degree from the U. of Manchester and is a cofounder and principal analyst at NanoMarkets LC, PO Box 3840, Glen Allen, VA 23058 USA; ph 804/270-7010, e-mail [email protected].