STUDY ELECTROMAGNETIC WAVE INTERACTION OF ACTIVE-MATRIX THIN FILM TRANSISTORS

Active-matrix thin film transistors (TFTs) on glass substrates with a metal backplane, that are applied for flat panel displays, can be considered as a metamaterial absorber. In this study, TFT structures using doped silicon at source, drain, and channel terminals are investigated. These terminals are unchanged in size of 75 µm square and thickness of 5.3 µm. The electric conductivity is varied at the channel. The simulation results show that the structures with 500 S\m electric conductivity channels absorb incident electromagnetic waves with appropriately 100% at 758 GHz and a wide bandwidth of 20 GHz. As the electrical conductivity increases, the absorption and bandwidth are smaller at the main resonance peak. As the electrical conductivity decreases, the absorption falls at the resonance frequency, but the bandwidth is broadened. In addition, the electric field in the channel may influence the electron in the semiconductor and the electrical current between the source and drain terminals. By observing the electric field at the resonance frequency, we found that it is focused on the sides of channel terminals.