On the Prospects of Stereolithography Method for 3D Printing of Future Microwave Devices with Low-Dk

The stereolithography (SLA) method is known for its high-quality surface finish and details, hence, gaining its popularity with the realization of 3D-printed parts and structures for microwave applications. On the other hand, low-dielectric
$(\boldsymbol{Dk})$
materials have an utmost importance in high-frequency PCB design and microwave applications. Here, the authors present the prospects of the SLA method in 3D-printing of
$\mathbf{Low}-\boldsymbol{Dk}$
materials for future microwave devices. The SLA method is a relatively new manufacturing process, so it is critical to explore a range of dielectric constants of a few prospective commercially available materials. Here, eleven different resin-based materials were 3D-printed as cubes using the SLA method and characterized in terms of dielectric constant
$(\boldsymbol{\varepsilon}_{\boldsymbol{r}})$
and loss tangent
$(\mathbf{tan}\boldsymbol{\delta})$
using broadband coaxial probe method. The measured dielectric constant values were within the range of 2 - 4 for all the tested materials which thus proved to be among promising candidates for realizing microwave devices in the frequency bandwidth of 1 to 20 GHz. A few observed failures while manufacturing certain other shapes were also reported as a limitation of the SLA method.