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Silver Inks for Printable Electronics

Compared with some of the exotic organic materials currently being used in printed electronics and the silicon and carbon nanotube inks that are just emerging, silver inks are a relatively mature product. Metallic inks have been used in graphics printing for many decades, although, of course, these silver inks were never intended to be used for their conductivity. There is also an established niche market for silver conductive inks, which have been used for some years to create certain parts of products such as heated mirrors, membrane switches, and medical devices. These differ from the devices that are usually considered to fall under the printable electronics heading in that only a small part of their manufacturing involves printing or is likely to. The products that NanoMarkets generally considers as falling into the PE category are functional devices that can be created entirely by printing, at least in principle.

In any case, because of this history there are probably more than 20 firms actively supplying conductive silver inks and the activities of these firms are reviewed later in this report. There activities, however, are still very much a cottage industry and while they offer "platform inks", these are typically highly customized to meet the needs of each customer. Clearly, the silver conductive inks firms will ultimately have to move away from this model, if PE is going to take off. However, for now other key technology trends are more visible in the marketplace.

from Silver Powders and Inks for Printable Electronics: 2007-2014 (NA-3022)

OLED Markets

Like other display types, OLED displays can be based on active or passive matrix technology. Today OLED displays are overwhelmingly passive matrix devices - perhaps 98 percent of the market is PM. Passive matrix OLEDs create a video image in a manner similar to that of a conventional CRT. Each pixel is addressed in turn over a 1/60-second cycle and some form of bistability is needed to keep the pixel "on" until the next sweep. To get the power needed for this approach to work requires high peak currents, which reduce the display’s lifetime. The number of rows over which this approach will work is limited to about 240. What’s more, the way in which pixels are addressed, by charging a cathode row and anode column (or vice versa), has an intrinsic high capacitance that has to be worked around.

Despite all these drawbacks, passive-matrix OLEDs will always be the cheaper alternative for some smaller, lower resolution applications. By contrast, with active-matrix OLEDs, there are no intrinsic limitations to pixel count, resolution or display size. Each pixel is addressed via transistor (usually a TFT), which not only allows pixels to be "on" or "off" over the entire frame/refresh time, but at a controlled brightness level, and potentially facilitates much more sophisticated control such as refreshing only the parts of the screen that have changed in each frame. Clearly for OLED displays to evolve into the high-performance markets in the manner predicted here, AM-OLEDs will have to become more widely available.

from OLED Markets: 2007 & Beyond (NA-3020)

Organic Electronics

Organic backplanes using OTFTs can be used as alternatives to current technology for backplanes for both conventional LCD displays and newer OLED and e-paper displays, both flexible and rigid. The market for LCD backplanes is already huge and is dominated by ITO, which is high cost. OTFT backplanes could potentially offer a way of reducing cost in this application and even a penetration of just a few percent of the LCD market by a printable backplane would generate sales of several million units.

Unfortunately, it does not seem that the LCD display industry has enough confidence in OE to switch from ITO any time soon. Organic backplanes would seem to be one likely backplane technology of choice for larger active-matrix OLED displays and flexible displays of all kinds. Manufacturers of organic backplanes continue to try to convince the big display makers to use organic backplanes, while looking to the OLED/e-paper/flexible display future for big opportunities. However, even for these new display types there are good alternative inorganic backplane technologies: amorphous silicon (a-Si) and LTPS (low-temperature polysilicon).

from Organic Electronics: A Market and Technology Assessment (NA-3019)

Photovoltaics and Thin-Film Technology

Thin-film (TF) technology has played a part in photovoltaics (PV) since the 1990s. Generally speaking, TF sacrifices some of the efficiency, but makes significant improvements in all the other areas in which traditional PV is limited. Nonetheless, the low efficiencies associated with TF PV along with the relative immaturity of certain materials platforms have meant that TF PV has never accounted for more than 5 to 10 percent of the entire PV market. However, the combination of better materials, the evolution of thin-film transitor technology, and new production methods combined with a surge in interest in PV in general because of high fossil fuel costs and global warming concerns has established TF PV as a hot area for investment in the past few years. TF has also enjoyed a lot of attention, because it gets round the current shortage of silicon that the traditional PV is currently experiencing, since, by definition, TF uses material than conventional PV.

from Thin Film and Organic PV: New Applications for Solar Energy (NA-3015)