Sub-micron features out of the 3D printer

March 02, 2016 // By CHRISTOPH HAMMERSCHMIDT
For research institutes and R&D departments in the industry that frequently have to provide prototypes of parts and features in sub-micron dimensions the Photonic Professional GT 3D printing system from Nanoscribe could be the right tool. The printer provides access to the highest-resolution additive manufacturing technology available today with layer thicknesses and feature sizes below 1 µm.

In the prototype phase within the product development process, it is often a priori not clear what the practical configuration of the micro-optical system will look like to enable optimum performance of the final product. For quick design iterations, developers therefore need rapid prototyping technologies to fabricate micro-parts, such as lens holders or mounts for miniaturized optical systems. Providing a better resolution than micro-stereolithography, the Photonic Professional GT system - which is based on 3D laser lithography - enables design freedom and quick design iteration cycles at a scale relevant for many applications in micro system technologies, that was previously unreachable.

 

Like all systems from this vendor, the Photonic Professional GT utilises two-photon polymerization of photosensitive materials as the starting material. Here, the mostly liquid resist is locally solidified by a photochemically triggered polymerization. The system employs laser light in the near infrared, to which the photoresist is transparent. The laser is femtosecond pulsed, leading to extraordinary high peak powers in the laser focus. Thus, the absorption of two or more photons is triggered, causing polymerization exclusively in this focus and not along the beam path. Unexposed material is easily washed out at the end. The resolution of this true 3D rapid prototyping process goes down to less than 500 nm and delivers complex, self-supporting microstructures.

 

This method also allows a high degree of flexibility because the computer-controlled beam guidance can transfer 3D CAD models directly into 3D structures of almost any complexity. Furthermore this has the great advantage that production costs and component complexity are largely decoupled.

 

More information: www.nanoscribe.de