High-Resolution 3D Printers Bridge the Gap Between Micro and Macro Scales

20 Nov 2018

Eggenstein-Leopoldshafen During this year’s trade fair formnext, the 3D microprinting technology and market leader Nanoscribe showcases the rapid fabrication of structures with micrometer precision in millimeter dimensions for the first time. Nanoscribe’s Photonic Professional 3D microprinters are mainly used for nano- and microfabrication. New advances in 3D microprinting allow short print times of the smallest structures in millimeter sizes.

Nanoscribe’s recent developments are shifting the limits of basic two-photon polymerization (2PP) technology to new horizons. The technology is now bridging the gap between micro and macro 3D printing in terms of build size and precision, as shown in figure 1. This achievement opens up new application fields in rapid prototyping of high-precision parts, biomedical engineering, and micromechanics.

Nanoscribe’s 3D microprinters outperform conventional 3D printers in resolution with the ability to print structures in sizes that range from a few hundred nanometers to several millimeters. These capabilities have triggered the development of novel devices, such as 3D microscaffolds for cell culture, compound lens systems on a CMOS sensor, and functional components such as gears, springs, and filters. Furthermore, the new macro-printing capabilities are used to fabricate devices such as nozzles, needles, and stent-like structures with a length up to several millimeters. The 3D-printed complex-shaped nozzle shown in figure 2 is characterized by an inner channel and a narrow opening, nearly 130 micrometers in diameter. This nozzle prototype paves the way for liquid jets, for example, as in gas dynamic virtual nozzles. The production of these devices benefits from the flexibility of determining the nozzle geometry as well as from the surface finish and the high shape accuracy provided by 3D microprinting.

The capabilities of Nanoscribe’s 3D microprinting enable submicron lateral feature sizes, and resolutions not yet available with other 3D printing techniques. Fused deposition modeling (FDM) and selective laser sintering (SLS) are limited in vertical and lateral resolution with layer thicknesses and smallest feature sizes in the range of several hundred micrometers. In the high-precision domain, stereolithography (SLA) as well as digital light processing (DLP) and polyjet are 3D technologies that provide sub-100 μm layer thicknesses. These techniques, however, may still face difficulties in the fabrication of high-precision parts of a few dozens of micrometers due to their limited resolution.

Improved printing perfomance

Nanoscribe’s 3D microprinting technology is a laser-based technology, in which a laser cures a photoresin material in a controlled layer-by-layer process. The gain in process speed is based on the interplay of matching components, such as a printing material, an objective lens, and software settings. The implementation of advanced printing strategies enables the laser to cure more volume per pass of the laser beam. Thus, the number of layers and the total print time for 3D structures decrease. As a result, the new capabilities represent a gain in throughput by a factor of 10 compared to previous print processes based on 2PP. Filigree scaffolds over several millimeter dimensions, as seen in figure 3, can benefit from these capabilities. This structure demonstrates an intricate design, now accessible by 3D microprinting. A deep look into this 3D scaffold reveals fine elements, much thinner than a human hair, that enclose numerous cavities in regular intervals within a structure.