Indium is a key component of Indium-Tin Oxide, the standard transparent electrode used in virtually all flat panel displays and microdisplays. An electrode is needed to either drive the cell or provide electromagnetic shielding, whether the display is a LC, OLED or plasma cell. Transparency is needed to allow the light generated or controlled to reach the outside world. Indium, however, is expensive and scarce and the demand is increasing rapidly. Could the shortage of indium put a limit on the FPD industry?

Matt Brennesholtz
Insight Media Analyst

According to Displaybank, the demand for indium was 861 tons in 2006, is expected to be about 1000 tons in 2007 and may reach almost 2000 tons by 2011. Indium is primarily produced as a by-product of zinc and lead production. By the standards of the zinc and lead industries, indium is small potatoes both in tons and in dollar volume, so they don’t always bother to refine it. Four years ago Indium was about $100/ kg and now costs $800/kg. A recent spike drove the price briefly to $1000/kg. Displaybank expects the total sales of Indium in 2007 to be $533M.

Flat panel displays are not the only users of indium. It is used in InGaAlP laser diodes, RoHS-compliant, lead free solders, touch-screen panels, thermal control coatings on window glass and in solar cells. There have also been reports of indium-based transparent transistors. Transparent electronics can’t be far behind!

Solar cells are growing in importance and have a distinct similarity to FPDs. For example, the recently announced Sharp Gen 10 fab for $3.2B will be used not only for LCD panels but for manufacturing solar cells as well. In one year, the fab is expected to be able to produce enough solar cells to produce 1000MW of power indefinitely. This is serious power, the equivalent of a medium-sized nuclear power plant. Is Sharp likely to close this fab due to a lack of indium? Not likely!

Insight Media sees three ways of easing the coming indium shortage. First, the existing zinc and lead miners are likely to recognize the economic value of indium and make more of an effort to refine it from their ores. Second, dedicated indium mines could be developed. While $533M may not be a big market to an established multinational mining company, it is a lot in terms of a startup.

Finally, substitute transparent electrodes could be developed that reduce the demand for Indium. One possibility was reported by Yu Mihara of Osaka University in Paper P-210 at SID ‘07. The paper covered Tantalum Tin Oxide as a transparent electrode, and discussed manufacturing processes, electrical properties and laser patterning techniques. Fluorine and Antimony have also been suggested as Tin Oxide dopants to produce transparent electrodes. Another SID ‘07 paper, 31.4 by Yoshihiro Fujita at Fujifilm, discussed a mesh approach using a silver-halide photographic process. While this couldn’t replace ITO in LCD panels, it could reduce the need for indium by reducing the demand by the PDP industry.

Carbon nanotubes can also be used as a transparent electrode. Unidym Inc., a subsidiary of Arrowhead Research Corporation, recently merged with Carbon Nanotechnologies, Inc., creating a powerhouse both in the R&D and patent licensing aspects of the carbon nanotube business. The combined venture is planning on pursuing carbon nanotubes for transparent electrodes, thin film transistors and field emission displays as well as for a number of other non-display applications. According to Unidym, the total market for transparent electronics is greater than $1B, of which the flat panel ITO coatings are only a part.

Even organic conductive polymers are being commercialized for ITO substitution, primarily for touch screens. Just ask Fujitsu about that.

Increased indium supplies and the availability of substitutes make it unlikely the LCD industry will ever need to turn away customers due to a lack of indium. That Sharp Gen 10 fab, with its 2,850 by 3,050 mm substrates, will probably find a way to operate, even with indium at $1000 (or more) per KG.

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