Yole: Organic Displays Still Seeking Scale

Vendors in the organic display technologies market are taking a page from the semiconductor industry and are developing toolkits that enable the manufacturing of organic displays on existing equipment, according to Yole Développement (Yole). This capability could mean the difference between widespread adoption of organic display technology or its limitation to niche markets.

“The OSC [organic semiconductor] industry is at a turning point and the next 18 months are going to be critical,” according to Yole’s analysts. Multiple panel makers are currently attempting to unroll organic thin film technology (OTFT) into older fabs. If successful, this would boost the credibility of the technology and the willingness of panel makers to invest and scale up. Many semiconductor manufacturers have fueled the use of their components by offering solutions-enabling toolkits to developers and customers.

Panels utilizing organic light emitting diodes (OLED) have been nirvana for OEMs seeking low-power, high-resolution displays that can also be produced on flexible substrates. Applications for flexible displays range from t-shirts to theaters. Since OLEDs can be applied to substrates using ink-jet technology, they are the first choice for manufacturing flexible displays.

However, the manufacturing infrastructure for TFT, now used widely for liquid-crystal displays (LCDs), is massive and cost-effective. Additionally, OLED inks and materials have had shortcomings, including inconsistencies in color and lighting; manufacturers have had difficulty scaling to large-sized OLED displays; and materials and equipment suppliers to the OSC/OTFT market are limited. A TV utilizing OLED technology is considerably more expensive than a comparable TFT LCD.

In order to enable OSC/OTFT, vendors have evolved from focusing on the commercialization of OSC molecules to offering full material packages and complete, fab-ready technology and process toolboxes, according to Yole. Full toolkits are now available that include all essential materials and processes to enable OTFT manufacturing with existing equipment.

The ability to cost-effectively produce large displays could be critical for the OLED market. “We estimate that the global demand for TFT display panels across all technologies will reach 188 million of m2 [a financial measure] in 2016 and increase to 238 million of m2 by 2022,” explains Dr. Eric Virey, senior technology and market analyst at Yole. Market demand is strongly dominated by large displays such as television and computer monitors. Smartphones come third despite their smaller area thanks to very high volumes. “Together, those 3 segments represent more than 90 percent of the total,” said Virey.

OTFT first commercial products could emerge in the following applications:

E-papers (e-readers and other applications such as signage, smart tags, etc.)
Embedded displays: automotive, industrial, etc.
Wearables

A wide variety of OTFT-based devices have been demonstrated: AMOLED, EPD, LCD displays as well as X-Ray imagers, fingerprint readers, and various types of sensors have been fabricated. In addition, multiple bricks of technology have been demonstrated for various types of electronics: inverters, ring oscillators, gate arrays, NANDs.

Most of the leading display makers are working on OTFT: LG, Sony, BOE, AUO, Chunghwa Picture Tube, etc. Many display makers have demonstrated a wide range of prototypes but none have released any commercial, mass produced products. The only notable exception is Plastic Logic, but the commercial success of its flexible EPD displays has so far remained limited.

OSC suppliers and OTFT makers have made significant advances in term of molecule performance, ink formulations and accompanying materials, according to Yole. Progress has also been made in TFT design, processes and manufacturing technologies. This has led to improved OTFT performance and manufacturability and compatibility with existing equipment. Plastic Logic was the first to enter mass production of flexible EPD based on OTFT backplanes in 2009.

Failure in the current attempts could be a fatal blow for the industry or at least, push back adoption by another 5 years, Yole warns. Indeed, panel makers would temporarily pull the plug on their industrialization effort and send OTFT back to the lab until all the technology bricks are ready for true flexibility or other, non-display applications emerge.

The “Organic Thin Film Transistor (OTFT) 2016: Flexible displays & Oher applications” report from Yole presents a detailed review of flexible displays, including an analysis of technical challenges, manufacturing status, key players, and technologies.