Design, fabrication, and characterization of rectangular split-ring resonators for sensing applications

In this thesis, rectangular split ring resonators in microwave and terahertz frequencies are modeled, fabricated, and characterized. For microwave frequencies, rectangular split-ring resonators with one-split and two-splits are analyzed. The resonators are coupled with monopole antennas for excitation. The scattering parameters of the devices are investigated under different polarizations of $\vec{E}$ and $\vec{H}$ fields. The addition of the second split of the device is investigated considering different configurations of the excitation vectors. It is demonstrated that the one-split and the two-splits resonators exhibit identical transmission characteristics for a certain excitation configuration. The presented resonators can effectively function as frequency selective media for varying excitation conditions. For THz frequencies, different designs of rectangular split-ring resonators with single-split are proposed. Three types of devices are fabricated utilizing a mask. In the first type, the resonators are made of copper and are patterned on Silicon substrate. In the second type, the resonators are made of copper and are patterned on a substrate composed of a layer of parylene on a Silicon wafer. In the third type, the resonators are made of titanium and are patterned on a substrate composed of a layer of parylene on a Silicon wafer. Each type of the devices is characterized and compared to the simulation results. Bio-experiments utilizing glucose are done for one of the samples. Due to electrical properties of glucose, resonances are shifted towards higher frequencies. Devices have the potential to be utilized as biosensors.