An expanding demand for such items as smart labels, mobile phone antennas, and disposable biosensors is driving a booming market for printed electronics. It’s a market that seems destined to grow as the technology evolves and the process is explored for countless additional uses.
The total market for printed, organic, and flexible electronics is projected to grow from more than $16 billion this year to $76.8 billion in the next 10 years, according to a new report from IDTechEx. Printed electronics will allow manufacturers to replace some components with cheaper, higher performing alternatives or even completely replace a conventionally-manufactured device.
Printed and flexible sensors are already a $6.3 billion business. The largest market is biosensors, used in disposable glucose test strips which are helping diabetics monitor their health.
Developers of printed electronics had to overcome significant technological hurdles.
“The gating item was the substrate,” said Ken Vartanian, Optomec marketing director, referring to early attempts to apply graphics technologies such as gravure, inkjet, and screen printing to printing electronics. “The ink had to cure at low temperatures to handle the variety of substrates.” Other limitations included thick ink viscosity, wide feature resolution, and the requirement to print on flat surfaces.
Advances in inks and substrate chemistries are creating a market for suppliers. Organic and inorganic components, including micro- and nano-particle compounds, can now be printed on a range of flat and uneven substrates. By sintering the inks instead of melting them, a variety of polymers, as well as gold, silver, and copper, can be joined to substrates at lower temperatures. The conductive inks can be deposited on such materials as polyester, polyimide, glass, c-Si, and a range of metals without altering the substrate.
“We are not trying to replace an entire conventional manufacturing process,” said Vartanian, “but rather add value to an existing process and make it as non-disruptive to a customer’s process as possible by replacing a functional step using a platform known to an industry.”
The resulting components, including transistors, antennas, circuits, connecting components, displays, sensors and batteries, are lighter and have more functionality than conventionally-manufactured electronics. “Printed electronics allow us to create functionalities on plastics and paper, and they will [continue to] decrease in cost as the process becomes faster,” said Janos Veres, program manager for printed electronics at PARC, a Xerox Co.
Printed antennas: reducing the need for complex automation
A recent IDC report forecasts the worldwide mobile phone market will grow 7.3 percent this year, spurred by overseas shipments of 1 billion smart phones.
Up to seven different antennas can be embedded in a single mobile device, said Vartanian. Optomec’s Aerosol Jet Printing Engine is in production trials as an alternative to laser direct structuring (LDS), the process currently used to manufacture mobile device antennas. The technology, which has already been used to print a range of antennas including LTE, NFC, GPS, Wi-Fi, WLAN, and BT, prints directly on the surface of a phone case using a silver nanoparticle ink. The one-step process can produce 30,000 units per week while eliminating a number of the environmental and health concerns related to the plating and nickel required by the multi-phase LDS. Optomec projects a cost savings of at least 15 percent over LDS.
Smart Labels: transistors, circuits and memory
Veres is particularly excited about the idea of form factors, such as the arrangement of entire arrays of sensors on a product. “In the long term, printed electronic devices will grow in complexity, although they will not take over the job of RFID,” he said. “They may even complement them in certain configurations.”
PARC has partnered with ThinFilm to create low-power, rewriteable smart labels with printed memory. These labels are flexible, creasable, and washable and Veres expects them to be used with wearable electronics that require multiple sensors. He anticipates smart labels being used as inventory tags for protection, identification, and security, and that they will be printed on packaging at the same time as an image, saving time and space.
Printed electronics have the ability to “insert step-by-step simple functionalities into products and form factors,” Veres explained, “where only a bar code could be considered before.”
Flexible & curved displays
In its original form, silicon is brittle. Printed electronics that use materials other than silicon “allow us to create coatings and layered structures with flexibility, that won’t break and have some stretch to them,” said Veres. He suggests that this flexibility, coupled with future development around smart labels, will lead to printed electronics that can bend, such as curved smart phone screens and flexible displays.
The organic light emitting diodes (OLEDs) market is another area of potential growth for displays. OLEDs, which are not currently manufactured via a printed electronics process, deliver advantages over LEDs and LCDs that include significant power savings and the ability to activate just one pixel. The chemistry is similar, said Veres, so perhaps it is only a matter of time. “The important thing is that the chemistry allows us to play with both the electronic properties (such as electroluminescence for light emission) and solubility (for printability), and there is a huge scope for material development,” he said.
Reaching the moon and beyond
Current work on printed electronics extends into outer space. PARC scientists are working with NASA’s Jet Propulsion Lab to develop what Veres calls “space confetti.” These heat and light sensors, printed on thin plastic sheets, are expected to transmit wireless information from space back to earth. NASA’s long-term goal is a 100-percent printed spacecraft.
Veres expects the inks, substrates, and processes used in printed electronics to impact a range of industries: material science, where development will focus on developing materials with added value; printing, where printing of books and paper will be replaced by printing of memory, sensors, and batteries; and consumer products, where an endless supply of electronic products will incorporate these materials and processes.
