In this thesis, EHD jet printing is used as an alternative fabrication method in tera-hertz metamaterial. Tera-hertz metamaterial requires sub micron resolution of periodic structures. EHD jet printing may print fine line patterning until sub micron resolution. It may have many advantages, becauseit eliminates the need for physical masks, reduces the fabrication costs, enables the fabrication of complex geometry,enables for large area fabrication and offers easy multi-layer fabrication. The main issues in metamaterial fabrication process are large size fabrication, high cost, contamination of sample and time efficiency. EHD jet printing may solve these issues. An EHD jet printing can produce droplets much smaller than the size of the nozzle size and can use very small nozzle diameter size. This unique feature distinguishes EHD jet printing from conventional methods for sub-micron resolution printing.
This thesis aims to understand EHD jet printing mechanism, understand tera-hertz metamaterial application, fabricate and analyze performance tera-hertz metamaterial. There are two phenomenain EHD jet printing mechanism: flight charge droplet behavior and EHD line printing stability, which were observed in this thesis. Depending on the type of applied electric field and net electric charge density of the droplet and surrounding area, charge droplet can fly directly to the substrate, retract to the meniscus, deflect from the original vertical line, or reflect after coming very close to the substrate in a deflected route. EHD jet printing can reduce droplet volume up to 18 μm3. Reducing the droplet volume enhanced the line printing region of stability; and increasing the droplet volume reduced the line printing region of stability.Fabrication of tera-hertz metamaterial with high refractive index and high absorber tera-hertz metamaterial by using EHD jet printing was presented in this thesis. Comparison simulation result and experiment result was presented in this thesis for validation performance of sample. Droplet on Demand (DoD) EHD jet printing was applied in fabrication process. To get DoD EHD jet printing, pulse DC signal was applied in EHD jet printing system. The peak of high refractive index value was achieved around 18.4 and 25.7 for single layer and multi layer tera-hertz metamaterial with high refractive index, respectively. The perfect absorber tera-hertz metamaterial samples which were fabricated by using EHD jet printing have good performance. The absorption achieved more than 99 %.