Developments in conductive micro additive manufacturing

Horizon Microtechnologies recently launched its template-based 3D-microfabrication technology, which produces conductive micro additive manufacturing (micro-AM) derived parts with micrometer scale precision.

At the Formnext 2022 conference, the company demonstrated its technology alongside micro-AM technology innovator Boston Micro Fabrication. Part of the demonstration featured the company’s post-build processes which introduced the versatility of micro-AM to such applications as electrodes and electrical contact pins, ESD safe parts, 3D microfluidics, and MEMS and optics packaging.

Template-based 3D microfabrication can effectively be a mechanism to exploit the usefulness of polymer micro-AM produced 3D microstructures (the template) for unserved areas of industry by adding material and function to the microstructure, typically with a coating process. The key enabling technology is micro-AM, and today a number of commercially viable polymer-based micro-AM platforms exist that can achieve exacting tolerances, quickly, cost-effectively, and repeatably. However, these platforms are almost exclusively restricted to the production of parts in resin or plastics. Horizon Microtechnologies bridges the gap between micro-AM and parts with enhanced function through the use of proprietary post-build processes. This means that companies requiring the flexibility, innovation, and agility that is driven by AM for parts with conductive, ceramic, heat-resistant, or other polymer-incompatible functionalities now have a commercially viable solution available.

Horizon specialises in the production of micro-scale conductive parts and environmentally resistant parts. To introduce conductivity, once the part is produced on a polymer-AM platform, it is either wholly or selectively coated with a conductive layer. Horizon can even coat difficult areas homogeneously such as long narrow channel and undercuts. Obvious application areas include electrodes, electrical sensor heads, and ESD-safe components.

Microfabricated 3D templates can also be coated with metal-oxides to make parts compatible with aggressive chemical environments and in some cases can increase the resistance to high temperatures and mechanical stresses. This allows, for example, the fabrication of nozzles and 3D microfluidics for aggressive solvents and certain acids with the full design freedom of additive manufacturing. In some cases, it is also possible to make bulk ceramic or glass objects.

When looking at ESD-safe parts, Horizon can make parts with a controllably conductive surface coating and coat internal channels with multiple bends. This allows the company to make compact and high-performance end-effectors for vacuum pick-and-place devices which are at the same time conductive enough to prevent ESD-discharge. ESD safety also enables the use of Horizon produced parts under conditions requiring spark-freedom and explosion-protection.

In the area of microfluidics, the additive manufacturing approach lends itself well to prototyping and small batch production of complex, multi-level microfluidic chips, including chips with integrated filters and interfaces to external components. Using Horizon’s post-print processes, the surfaces in contact with the liquid can be coated to improve wetting behaviour, control surface energy, or even introduce electrically conductive areas.

Finally, while AM is not typically considered a mass-production technology, the reduction in the size of electronics and optics — and the accompanying shrinkage of packaging — has made it a viable production alternative for MEMS and optics housings for small to medium batch sizes. In addition to the precision offered by micro-AM, an intelligent use of Horizon’s post-processes can increase the functionality of the packaging, for example by reducing stray light in the infrared, or by having integrated electrical conductors.

Horizon Microtechnologies
www.3dmicrofabrication.com