The Effect of Conductive Ink Layer Thickness on the Functioning of Printed UHF RFID Antennas

In this study, the effect of the conductive ink layer thickness on the performance of printed ultra-high-frequency (UHF) radio-frequency identification (RFID) tag antennas was investigated. A simple quarter wave dipole tag for European UHF RFID frequencies was designed to be tested in this study. All the tags were made by using screen-printing technique. Three different thicknesses for the ink layer were used. Performance of the tags was analyzed by the measurement of threshold and backscatter power. The results show that it is possible to produce RFID tag antennas by screen printing and it is possible to optimize the tag performance by adjusting the thickness of the electrically conductive layer. The results show how the performance characteristics deteriorated when the thickness of the printed ink layer was reduced. However, it was also shown that thin ink layers can be used in some applications and cost savings can be achieved in this way. It is therefore important to recognize these effects on the performance.