Components have traditionally been discrete packages that are constructed from materials and pieced together. For example, carbon film resistors consist of a controlled amount of carbon and impurities compacted into a casing with a pair of component leads attached.
Integrated circuits are devices that are created layer by layer, cut into individual dies, placed into IC packages and then wired up to their respective pins. But there is growing interest in 3D printing technologies which have the potential to replace many electronic components.
Printed Electronics (UK) flexible fabric with LEDs. Image courtesy of Printed Electronics Limited.
3D printing (also known as additive manufacturing) actually dates back into the 1980s where experiments were done using UV light and photo-sensitive resins. During this time, just about every form of part machining was done with subtractive methods which involve removing unwanted material from a workpiece (for example, making a sculpture from a block of marble is done by removing unwanted material).
However, it would not be until the early 2000s when 3D printing of parts started to become a real alternative form of manufacture.
With the rising success of 3D printing technologies, the increase in appeal, and lower costs in parts such as stepper motors and controllers, it is no surprise that printed electronic components are becoming a reality.
- Working with High-Temperature 3D Printer Filaments
- HT vs PLA Filament for High-Temperature 3D Printing
- 3D Printing Filaments: HT vs PLA Final Overview
- OLEDs and flexible displays
Optomec Aerosol Printing
Optomec is a company that produces 3D-printed electronic parts for a range of applications. Their system can print commercially available conductive, dielectric, semiconductor, and biological inks directly onto common substrates such as ceramic, plastic, and metals.
Printed electronics have many advantages over traditional components such as:
- No need for stencils, masks, or custom fabrication equipment
- Components can be made to a custom specification
- Finished circuits can potentially be smaller
- Changes to designs can be implemented much more easily
- Removes the issue of obsolete parts
Optomec System printing thin connections 25um wide. Image courtesy of Optomec.
Here at AAC, we asked Director of Optomec Mike O'Reilly for some insight on what their current capabilities are with their Aerosol system. O'Reilly's response gives a glimpse into the level of ambition that the company has for its technology.
"Optomec specializes in the ability to print 3D conformal circuits for a variety of consumer electronics and industrial applications. We can help make devices smart and connected. We have relevant experience with materials, scalable printing technology, and 3D tool path generation to produce functional electronics that can be used from proof of concept through initial prototypes to full high volume production."
The Aerosol system works in three stages:
- Atomizer – This turns the ink into droplets between 2 to 5 microns in diameter
- Virtual Impactor – This removes excess gas from the mist made by the atomizer
- Deposition Head – This uses a gas to sheath the mist and deposit the ink onto a substrate
Aerosol's three main parts for atomization and controlled deposition. Image courtesy of Optomec.
Applications of Printed Electronics
Printed electronics are finding their way into many areas of engineering, ranging from high-tech military applications down to the smallest consumer products.
One example of the potential of additive manufacturing is the fabrication of antennas in smartphones. Normally, a wire or PCB trace is used as an antenna for Wi-Fi and cellular networks but these can be problematic for their height profile and use of precious PCB space.
Instead, these antennas could be directly printed onto the phone case which helps to reduce the size of devices and thus drive down cost.
Aerosol-printed antenna on smartphone case. Image courtesy of Optomec.
Optomec is not the only contender in the printed electronics industry. DuPont has a range of inks for printed electronics which include silver conductive inks, low-temperature inks for use in electronics, and ink that stretches (which could be hugely important for the development of wearables).
Another company that is researching this technology is Printed Electronics Limited in the UK. Their involvement with printed electronics includes electroluminescent displays, flexible materials, and implanting electronics onto most surfaces.
The drawing outline (left) and the finished result (right). Image courtesy of Printed Electronics Limited.
The Future of Printed Electronics
With the ever growing market for smaller, cheaper devices, it will not be long before additive methods such as Optomec’s Aerosol system begin to become mainstream methods for manufacture.
Flexible electronics, conductive inks, wearable circuitry—printed electronics are almost certainly going to become a larger and larger part of the projects that we develop and buy.
According to Optomec's Director, Mike O'Reilly, their Aerosol system ultimately has the power to advance the IoT:
"Our products are currently used in 24X7 manufacturing for applications ranging from 3D-printed smartphone antennas to printing a wide variety of sensors on conformal components. These sensors are finding their way into condition-based maintenance applications helping to fuel the Industrial Internet of Things."
To learn more about the Aerosol printing technology, check out this video: