Wideband Micromachined Patch Antenna
A rectangular patch centered over a cavity and fed by a microstrip line on high index Silicon based substrate is investigated using micro-machined technology. This fabrication technique is used to laterally remove the material underneath the specified cavity region. It has been observed that bandwidth increases from 2.9% for the regular antenna to 5% for Micro-machined patch. In this paper, cavity model is used to predict the effective dielectric constant of the mixed air-silicon region. A quasi-static model based on series capacitance is used to determine the patch capacitance. Effective dielectric constant of 2.2 is achieved for a mixed air-silicon ratio of 1:1.