We believe some applications will be more likely than other to be successful – for example, bendable applications will undergo tough stress during use and technological challenges will be hard to overcome. Our report shows the distinction between the functions (displaying, lighting, energy conversion, sensing & substrates) and the seek flexibility “degree of freedom”. We do not make the distinction in our report between organic and inorganic substrates as semiconductors can also be used as flexible substrates.
However, we believe over the next several years, the number of applications using printing processes for flexible electronics will grow (Figure on page 2).
We estimate the printed & flexible electronics market will grow from ~ $176M in 2013 to ~$950M in 2020 with a 27% CAGR in market value. Printed OLED displays for large size (TVs) are likely to become the largest market. For OLED lighting, we believe it will grow but remain a niche market for automotive and/ or office lighting. For PV, the market demand by 2020 will remain very low compared to the demand for rigid PV, largely below 1% of the global market demand by 2020.
Sensor, smart system & polytronic applications will include sensors, touchless / touch screens, RF ID applications.
A WIDE, EXCITING RANGE OF NEW APPLICATIONS
Printed & flexible electronics is a new exiting technology with large potential market expectations. Indeed, as semiconductors move to the very small with 22nm critical dimension, printed electronics moves to the other end of the spectrum with its own material, equipment, process challenges and supply chain. Printed electronics will not kill semiconductor electronics as it will not be a replacement for CMOS silicon. However, it will create new industry segments and new classes of applications with unique features, benefits and costs that cannot be addressed with conventional semiconductor electronics.
For example, we believe printing technologies will also allow additional properties such as flexibility. Originally, the general vision for printed electronics was the possibility to print low cost electronic components on any substrate. It was supposed to allow low cost, low efficiency, large volume electronics manufacturing, and it was supposed to create a large multiplicity of applications. Flexible electronics appeared quite soon after envisaging printability. Such devices were supposed to allow new applications directly linked to flexibility.
Moreover, the coming of polytronic technologies is a disruptive approach that could change the way printed & flexible electronic devices will be manufactured. It can be considered a new alternative to the “More Moore” approach where Si ICs, thin films, micro batteries, displays etc … will be embedded in a flexible substrate. The global interest in polytronics is born from the difficulties faced by the flexible & printed electronics industry. It is an alternate way to come to similar results while trying to avoid some of the main challenges.
MANUFACTURING: KEY PROCESSING CHOICES ARE STILL TO BE MADE
We have identified strong technical challenges for the printed & flexible electronics industry to overcome if it is to be successful. Today it is still more technopush rather than market-pull. Printed and flexible electronics are still looking for high throughput, high resolution deposition techniques in order to become suitable for other markets than just a few niche highend applications. For example, a big bottleneck is an efficient barrier technology. Indeed, to be successful, the main technical challenge in the short term lies in finding a good barrier technology: encapsulation materials are not so good on flexible substrates.
Solution printing process flow is composed of three main steps: ink/coating creation, deposition and curing. Ink chemistry is application dependent, and various precursors can be used for the same application. The nature of the ink / coating will define what kind of process can or cannot be used. For example, only inks containing very thin particles can be used for inkjet printing (typically < 100nm particle for 1μm diameter nozzles). In the same way, deposition methods induce specific requirements in terms of viscosity. Deposition techniques vary, but most of them are not yet adapted to large volume, low cost printed electronics. Thermal processing is required in order to crystallize the ink. Curing temperature and time are critical factors for printed electronics manufacturing as organic materials are very sensitive to high temperatures.
For printed and flexible electronics, every application has its own challenges. For example, flexibility challenges for small screen OLEDs are: