Trenched Silicon Microstrip Antenna Arrays with Ground Plane Effects

In this paper wet etched micromachined trenches with conductor hangovers are used along the radiating edges of series-fed microstrip patch arrays fabricated on a high resistivity (10 k¿cm) silicon. Such arrays are suitable for integration into advanced mobile wireless products. Experimental and simulation results show that these trenches reduce the effective dielectric constant of the substrate and improve the antenna radiation patterns. It is shown for these antennas that conventional backplate metallisation evaporation procedures require special masking and are therefore expensive to implement The effect of alternative backplane configurations is discussed in detail and it is suggested that a separate intimate ground plane is necessary for optimal trenched array performance.