By Jeff Dorsch

In wearable gadgets, flexible electronics may have met its dream application. And that’s no stretch of the imagination.

For example: The 711^th Human Performance Wing of the U.S. Air Force is looking at sweat sensors that could be embedded in a printed electronic plaster and attached to the arms of pilots to monitor whether they need to drink more fluids or if taking amphetamines would be advised to maintain optimal alertness in flight.

IDTechEx has forecast that the worldwide market for flexible, printed, and organic electronics will increase from $16.04 billion last year to $76.79 billion in 2023. The overall market will continue to be dominated organic light-emitting diode displays this year and in 2015, the market research firm predicts. Conductive ink and photovoltaics represent large segments of the total market. “On the other hand, stretchable electronics, logic and memory, thin-film sensors are much smaller segments but with huge growth potential as they emerge from R&D,” IDTechEx states.

Printed and flexible sensors are a $6.3 billion market, according to IDTechEx, with much of that total representing biosensors – disposable blood-glucose test strips that diabetics use to check their blood-sugar levels.

Frost & Sullivan forecasts that the printed electronics market will enjoy a compound annual growth rate of 34 percent through 2021.

Semiconductor Equipment and Materials International has taken a large interest in flexible and printed electronics for several years, establishing the SEMI Plastic Electronics Special Interest Group. In cooperation with FlexTech Alliance, SEMI will present a SEMICON West workshop on Thursday, July 10, on “Flexible Hybrid Electronics for Wearable Applications – Challenges and Solutions,” commencing at 10 a.m. at the San Francisco Marriott Marquis Hotel.

SEMI also will stage the annual Plastic Electronics Conference and Exhibition on October 7-9 in Grenoble, France. The plastic electronics show will alternate between Grenoble and Dresden, Germany, in the years ahead.

Belgium-based imec has been working with thin-film materials in flexible electronics – not the generally inflexible silicon, but indium gallium zinc oxide (IGZO), according to Philip Pieters, imec’s business development director. It is a very thin, flexible, unbreakable material, and “almost invisible,” he says.

IGZO thin-film transistors were first developed more than a decade ago by the Tokyo Institute of Technology and the Japan Science and Technology Agency. The IGZO-TFT technology has been licensed to Samsung Electronics and Sharp Electronics.

“We could make microprocessors, AC/DC circuits, etc.,” with IGZO, Pieters says. “Our processes are compatible with large-format glass plates. It could be processed in a cost-effective way for large-scale manufacturing.” IGZO could prove to be cheaper than silicon-based electronics, he adds.

As a research and development organization, imec keeps its production of IGZO-based electronics on a small scale, but the process could be ported to large-scale plants “in the next year or so,” Pieters says.

Stretchable electronics that “could be put on skin” are one potential application in wearable devices, the imec executive adds.

Printed, flexible, and organic electronics are clearly a growing opportunity, one that is attracting an increasing number of manufacturers and suppliers.