Transparent UHF RFID tags based on CVD-grown graphene films

Abstract

Ultra-high frequency (UHF) radio frequency identification (RFID) tags need to be attached or embedded to objects in various environments to achieve non-contact automatic identification. Graphene shows unique electrical and optical properties, which makes it become a promising material for radio frequency devices. In this paper, the transparent UHF RFID tags were fabricated based on graphene films with different number of stacked layers prepared by chemical vapor deposition (CVD). Through structural design, parameter optimization and experimental measurements, the reading distance of the transparent RFID tags was tested and compared. As the graphene film stacked layers increased, the reading distance of graphene-based RFID tags was farther. The UHF RFID tag based on the CVD-grown graphene with the light transmittance of 88% reached the maximum reading distance of 2.78 m in the frequency range of 860-960 MHz. In addition, the reading distance of graphene-based RFID tags at different bending angles and cycles was measured. The results reveal transparent graphene-based RFID tags have good flexibility and stability and can be used in flexible transparent devices.

Optically Transparent and Mechanically Flexible Coplanar Waveguide-fed Wideband Antenna Based on Sub-micron Thick Micro-metallic Meshes

“…But the thick TCO layers are unfriendly to the mechanical flexibility, and bending tests have not been reported for the AgHT-based transparent antennas [13][14][15]. Carbon-based materials, e.g., conductive polymers [16,17], graphene [18][19][20][21], and carbon nanotubes (CNTs) [22], have been reported for transparent and flexible antennas. However, due to the high resistances of the transparent thin films, the radiation properties of the antennas cannot compete with those of the TCO-based antennas [5][6][7][8].…”