Master of Engineering Science
Mechanical and Materials Engineering
Recently, metasurface plays significant roles in manipulation of electromagnetic waves. The main fabrication methods are MEMS (Microelectromechanical systems) technology and PCB (Printed circuit board) technology. Both methods face the challenges of complex fabrication processes, high cost, and severe pollution. In this thesis, the digitalized reaction on demand (DRoD) method, as a new printed electronic technology, was proposed to address the problems. In this method, the substrate was coated by PVA and nanoparticle composite to form a mesoporous ink absorption layer, followed by reduction functionalization. A novel silver ink was formulated to solve the problems of low conductivity, nozzle blocking, and complex preparing processing. As a demonstration, EM metasurface was fabricated via digitally and precisely control of silver reduction reaction. Moreover, a roll to roll process of metasurface printing via DRoD method was demonstrated. The developed technology provides a solution to produce metasurface with low cost, high quality, and large scale.
Summary for Lay Audience
Electromagnetic (EM) wave is the fundamental element in the modern society. The manipulation of the EM wave, mainly including selective absorption and reflection, will play an essential role in the development of many applications, like high-frequency communication, Internet of Things, and human-machine interface. The metasurface is the artificial structure with the period patterns. The manipulation of the EM wave via metasurface is realized by the resonance frequency of metasurface. The performance of the manipulation performance of the metasurface is greatly affected by the manufacturing process. The MEMS (Microelectromechanical systems) technology and PCB (Printed circuit board) technology take the dominate position for the fabrication of the metasurface. MEMS technology requires complex fabrication processes, expensive equipment, and long preparation period. PCB technology has the limitation of low flexibility and high pollution in the whole fabrication process. To solve the problems above, a new printed electronics technology, digitalized reaction on demand (DRoD) method, was proposed and demonstrated. In the DRoD method, the substrate was treated to form a mesoporous ink absorption layer in the first step. Then, the reduction coating layer functionalized the substrate via Mayer rod coating. High concentration silver salt ink was formulated to simplify the preparation process, reducing the production cost, and avoiding pollution. Inkjet printing was applied to form the metasurface with high conductivity by the digitally controlled in situ reduction reaction of silver salt ink. Such an approach shows great potential in the roll to roll production process. The primary step of the roll to roll printing system was realized, and a novel system for the roll to roll printing based DRoD method was designed. The developed technology in this thesis provides a creative way to produce metasurface with high efficiency, low cost, high quality, and large scale.
Gao, Jishu, "Electromagnetic Metasurface Fabricated by Printed Electronics and Its Applications" (2020). Electronic Thesis and Dissertation Repository. 7178.