Characterization of polymer silver pastes for screen printed flexible RFID antennas

Rapid development in the field of printed electronics, especially in radio frequency identification, provided new environmentally friendly, high throughput and cost effective manufacturing techniques of electronic components, such as RFID transponders. To continue this trend, the materials and their effect on the properties of printed components are necessary to be examined. In this paper, polymer silver pastes deposited on flexible substrate with screen printing technique were characterized with respect to RFID antennas. A modified dipole for UHF frequency range was designed and simulated in IE3D. Then, it was fabricated with a screen printing technique on two types of flexible substrates, i.e. foil and paper, using the polymer pastes with silver flakes. A resistance, thickness and average surface roughness of the manufactured antennas was measured. In addition, their power reflection coefficient was analyzed to evaluate the performance of screen printed UHF RFID antennas.