Three-dimensional μ-printing: An enabling technology

In this progress report the development of three-dimensional μ-printing and its impact as an enabling technology onto different scientific fields is reviewed. Driven by direct laser writing via two-photon absorption, the technology has reached a level of maturity and ease of application such that 3D printing on the micrometer scale can now be considered. While the underlying technology is still developing towards higher resolution and increasing speed of fabrication, the last five years have seen new fields rising that were obviously enabled by 3D μ-printing. Among the recent technological developments discussed in this progress report are the fields of super-resolution lithography and spatial light modulator-based lithography. Novel fields relying on these technological advances like aperiodic photonic structures, mechanical metamaterials, and structures for biological studies will be reviewed. A glimpse into developing research directions will also be provided