Designer’s Notebook
Next-Generation Additive Manufacturing
Non-planar designs and side-mounted components are next up for 3-D printing.
It is true that even today, so many years after 3-D printing started to garner attention and acclaim, rapid prototyping remains the single most common use for 3-D printers. 3-D printers offer advantages in the form of shorter turnaround times, improved development secrecy and greater design freedoms. But it is also true 3-D printing isn’t going to remain primarily a tool for rapid prototyping much longer.

Those keeping abreast of events in the worlds of design, construction, manufacturing or medicine will be keenly aware of the impact of additive manufacturing in these fields. Certain products have been rapidly affected by the arrival of additive manufacturing. Prime examples are hearing aids and dental aligners. Both markets have been transformed by the adoption of 3-D printing technologies. Additive is now the default manufacturing technology for such products.

Now, the emergence of additive manufacturing to make final parts correlates well with products that require:

  • Customization (where individualization is a priority, such as dental aligners and hearing aids)
  • Small volumes (where scaling to mass production is not a priority)
  • Difficult logistics (distributed in-situ manufacturing such as in space or other remote locations)
  • Highly complex parts that cannot be made using traditional methods (such as GE’s advanced jet nozzles).

The arrival and evolution of additive manufacturing in the mechanical world is something people are now familiar with. That it is beginning to have a similar impact in other domains such as medical and electrical functionality is becoming more obvious. The underlying advantages remain the same, but the systems and materials required to deliver the results are very different.

What makes additive manufacturing of electronics different? For additive manufacturing to make inroads into the world of electronics requires several ingredients the traditional additive manufacturing toolset doesn’t include. Resolutions need to be better; multiple materials need to be printed simultaneously in the same machine, and materials must support high temperatures and have specific dielectric properties.

For additive manufacturing to provide a compelling offering to the electrical engineer, the approach must deliver ways to speed prototyping, bring it in-house and open doors to entirely new ways of designing and manufacturing electronics. The same recipe that has brought much success to 3-D printing is now in place to do the same to this new electrical domain.

Deposition of materials is key. An additive manufacturing approach is clearly based on precise deposition of materials. This is a layer-by-layer additive process, whereby specific materials are placed in specific locations to build up an integrated functional part in a one-system print process.

For an engineer looking to speed current R&D cycles, this means bypassing much of the waiting involved in traditional outsourced prototyping. Going from design to functional part in a matter of hours can change how innovators and R&D groups practice their craft. This can get a validated circuit board from PCB design much more quickly. Given the flexibility of additive manufacturing, the engineer can also consider electrical applications beyond traditional PCBs, including designs for antennas, printed capacitance, electromagnets and molded interconnect devices (MIDs).

Rapid progress from design to part. To be clear, additive manufacturing of electronics is not limited to PCBs. It is also used for other types of application development, including devices with new requirements and increasingly complex formats. It’s an ideal fit when faced with geometrical complexity, portability and very small dimensions, such as those for semiconductor applications, medical devices, Industry 4.0, the Internet of Things, etc.

When designing a standard planar PCB, operating a 3-D printer doesn’t require anything other than the traditional Gerber and Excellon output files. Traditional EDA PCB design packages are focused on meeting the needs of today’s electrical engineers. This means the ability to design circuits and systems of circuits that are rigid or flexible, planar, multilayered, high-speed-compatible and so on. All these can then readily output files that can then be used by the 3-D printer.

A new way of thinking. Additive manufacturing is now leading to new ways of thinking about old challenges. Some of these require design tools that can design in the third dimension and design new capabilities.

  • Capacitors. Additively manufacturing capacitors within the layers of a circuit can create space to meet miniaturization requirements. With extra space, designers may pack more functionality on the board and shrink component size – all without compromising reliability.
  • RF circuits. Harris Corp. has additively manufactured 6GHz RF amplifier circuits, and found they worked as well as those created with traditional methods.
  • Side-mounting technology. Recently, Nano Dimension announced a world’s first side-mounting technology for additively manufactured PCBs. Using a 3-D printer to create a circuit board, components were placed on the top and bottom of the PCB, as is traditionally done. Components were also added to the sides, resulting in as much as a 50% increase in board space compared with traditionally manufactured PCBs. 3-D printing mounting allowed design engineers to pack more functionality on the board.
  • Ball grid arrays. Modern printing technology can shorten and simplify the assembly process for BGAs and other SMT components. In a proof-of-concept testing, the time needed to create and populate PCBs with BGAs went from days or weeks to just one hour. Typically, the process from initial design through printing, soldering, manufacturing, assembly and reflow takes weeks to complete. With a special layout structure that can be achieved only through additively manufactured PCBs, there is no need for special tooling for assembly. This enables in-house manual assembly of BGAs and SMT components during the design and application development phase.
A cutaway rendering of a 3-D printed board
Figure 1. A cutaway rendering of a 3-D printed board.
Samples of 100% precision 3-D printed products
Figure 2. Samples of 100% precision 3-D printed products.
“Going from design to functional part in a matter of hours can change how innovators and R&D groups practice their craft.”
Where are we heading? Additive manufacturing of electronics, whether circuits, antennas or components, is very much a reality. No doubt we are in the early days of the revolution, but 3-D printing electronics is here. Developing and deploying increasingly rapid, reliable and material-agnostic printers will only further use of this technology. The addition of a broad range of advanced, 3-D printable materials and sophisticated electrical design packages capable of truly non-planar electrical design and simulation will see this grow to an everyday part of the electrical engineer’s toolkit.
Simon Fried
Simon Fried
cofounded Nano Dimension and has worked as a consultant on projects covering sales, marketing and strategy across the automotive, financial, retail and telecom industries.