Micromachined periodic surfaces for planar terahertz antennas

In this paper we present micromachined periodic partially reflective surfaces (PRS) employed in the design of planar Fabry-Perot type antenna for terahertz frequencies. The fabrication process is based on micromachining and metalizing multiple SU-8 photoresist layers. A resonant cavity is formed by placing the PRS over a single waveguide-fed aperture in a metallic ground at a distance of about half wavelength. A square aperture array within a metalized SU-8 layer is used as the PRS, and the dimensions are optimized using full wave simulations (CST Microwave Studio^TM). A high gain antenna operating approximately at 284 GHz has been designed and a prototype has been fabricated.