A multi-material 3D printing approach for conformal microwave antennas

In this paper a new approach for implementing conformal antennas using direct digital manufacturing is presented. The new approach is based on fused deposition printing of a 150 micron-thick thermoplastic layer on top of Kapton tape forming a smooth, thin and flexible substrate. The antenna metallization is then printed on the smooth face of the flexible substrate using micro-dispensing, and the substrate is subsequently adhered to a 3D form. This approach represents a simple and versatile method for building microwave components as 3D structures. A 6 GHz 3D dipole is presented as an example to validate the fabrication approach. An acrylonitrile butadiene styrene (ABS) substrate (relative permittivity of 2.7 and a loss tangent of 0.008) and Dupont CB028 silver paste are used to fabricate the dipole antenna.