Cambrios’ ClearOhm Material Makes Major Inroads into Touch Screen Market

Printed electronics manufacturers have become an integral part of the touch screen technology industry. As touch screen makers continue to improve touch screen responsiveness, they increasingly seek and incorporate new technologies that can, and are currently being successfully utilized in commercial products.

Cambrios Technologies Corporation is very much at the forefront of touch screen technology. Indium tin oxide (ITO) remains the leading conductive technology, despite its numerous limitations, including brittleness, which makes it difficult to use on flexible substrates. Formed with highly conductive silver nanowires, Cambrios ClearOhm™ coating material is the only commercially-available transparent conductive solution with performance superior to that of ITO.

Cambrios marked the first commercial implementation of its ClearOhm transparent conductive film in 2011, when a leading smartphone manufacturer incorporated the material in its touch sensor. Cambrios’ ClearOhm materials now appears in a host of products, including the LG Electronics’ V325 Windows 8-certified All-in-One PC, LG Touch 10 ET83 and ET63 touchscreen monitors, GVision’s L15AX POS display, and the popular NEC N-07D Medias X Smartphone, sold on the DoCoMo network in Japan.

Cambrios Technologies has gained significant momentum since Dr. Angela Belcher of the Massachusetts Institute of Technology and Dr. Evelyn Hu of the University of California, Santa Barbara, founded the company in 2002.

“Their vision relied upon the use of nanostructured inorganic material, fabricated and shaped by biological molecules, to create novel materials and processes for a variety of industries,” said Rahul Gupta, Cambrios’ senior director of business development. “Through extensive research and development, the Cambrios team discovered two main attributes of its technology: its unique ability to synthesize inorganic materials from soluble precursors and the capability to assemble inorganic materials into functional nanostructures.

“Cambrios’ scientists seized the idea of making electronic materials using these proprietary nanostructures and developed Cambrios’ ClearOhm material, a solution- processed transparent conductor,” Gupta added.

ClearOhm can be coated at low processing temperatures (< 120C) to create a flexible transparent conductive layer on various substrates such as glass or plastic. It is compatible with industry-standard coating equipment and can be deposited through a high speed, high output roll-to-roll coating process.

Cambrios began to productize its conductive material in 2004 after receiving Series A funding. The company continued to grow through venture funding, including $5 million from Samsung Venture Investment Corporation, and opened branch offices in Japan and Taiwan in addition to its Sunnyvale, California headquarters.

Concern over ITO’s limitations for flexible substrates remains a key driver for the increasing interest in Cambrios’ ClearOhm materials.

“Smartphones, e-readers, OLED televisions and other printed electronics technologies have advanced to the point that ITO, the standard transparent conductive material used to enable these markets, now limits future development,” Gupta noted. “ITO is expensive and in order to achieve low resistance, uses glass substrates that are fragile, heavy and thick – entirely unsuitable for the next generation of lighter, thinner, flexible and curved devices. Growing concerns about ITO’s capabilities have led ODMs and OEMs to seek alternative materials, and Cambrios’ ClearOhm transparent conductive material has emerged as the leading ITO alternative.”

Currently, transparent conducting materials enable a variety of applications including displays (LCD, OLED and epaper), touch sensors, semiconductor lighting (LED and OLED) and solar cells. Many of these applications require low resistance coupled with high transparency, and manufacturers prefer to employ processes or form factors that use a transparent conductor on a flexible substrate rather than rigid, expensive substrates such as glass. Gupta noted that ClearOhm technology excels because its low temperature roll-to-roll solution processing enables low resistance (<10 – 300 ohms/sq) with excellent transparency, even on plastic substrates such as PET.

“Unlike ITO, ClearOhm material is very flexible and enables the development of unbreakable and flexible products,” Gupta added. “Companies seek Cambrios’ technology for many applications where thin, light weight, shatterproof designs are important.”

In particular, the printed electronics industry has recognized Cambrios’ contributions to the touch panel market. Notably, ClearOhm coating material won the 2012 IDTechEx Printed Electronics Award for Product Development.

“The launch of Windows 8 is driving the adoption of touch screens on laptops and all-in-one computers,” Gupta said. “The larger size of these devices compared to smartphones requires a low-resistance transparent conductor to maintain the highly-responsive touch experience consumers demand on much smaller phones. ClearOhm-coated PET with resistance as low as 30-80 ohms/sq, a resistance range unachievable with ITO sputtered on plastic substrates, is already enabling touch sensors for all-in-one PCs. The cost effectiveness of touch sensors made using Cambrios’ ClearOhm technology is driving faster mass-market adoption of touch-enabled laptops and all-in-one PCs.”

In addition to enabling innovation within the large area touchscreen market, Cambrios has made significant strides with OLED lighting and solar cells.

Cambrios has demonstrated high-efficiency OLED lighting with efficiencies of more than 40 Lm/W using ClearOhm electrodes, which also improves angle dependence of color, resulting in better displays and lighting products.

ClearOhm material currently enables high-volume, low-cost roll-to-roll production of efficient solar cells. Together with flexible thin-film solar module developer Ascent Solar Technologies, Inc., Cambrios demonstrated effective copper indium gallium selenide (CIGS) solar cells using its wet-processed, transparent conductive ClearOhm material. In addition, ClearOhm material is in pilot qualification for high throughput roll-to-roll production of OPV devices and has the potential to improve the performance of photovoltaic (PV) modules.

Gupta noted Cambrios has been working on ClearOhm transparent conductor technology since 2005. Key developments focused on improving performance by decreasing the haze of the ClearOhm layer, improving reliability, and scaling to high-volume production.

“Since Cambrios is targeting high-volume consumer applications, one of the key developments has been to scale up production so that the company can meet quick production ramps and leverage economies of scale to bring costs down for customers,” Gupta said.

In addition to the several commercially-available devices using ClearOhm material, Cambrios’ success can be gauged by the company’s strong engagements with many other large companies.

“Cambrios continues to build strong partnerships that will ensure our success not only in the touch panel market, but also in many other emerging markets,” Gupta said. “LG has announced several end products that consumers can now buy in the market. Samsung and many other strategic customers have made large investments in the company, and we are confident that ClearOhm material will continue to gain market share and eventually replace ITO as the go-to transparent conductive material for numerous applications.

“The printed electronics industry is still very young,” he added. “The market has seen some early products such as epaper, touch panels and sensors, but there are many innovative products being developed, including efficient OLED lighting, OPV devices and flexible displays.” These innovations must cost effectively deliver exceptional performance in order to reach mass production and broad consumer acceptance.

“Cambrios remains optimistic that this market will grow significantly over the next decade, and we hope to continue to play a key role in enabling many of these products,” Gupta concluded.