Millisecond pulsed light annealing for improving performance of top-gate self-aligned a-IGZO TFT

Abstract

The application of millisecond intense pulsed light (IPL) annealing to improve the electrical properties of top-gate self-aligned (TG-SA) amorphous indium gallium zinc oxide (a-IGZO) thin-film transistors (TFTs) was investigated. The IPL annealing with a pulse energy of 40 J/cm(2) and a pulsewidth of 20 ms resulted in 53.7% increase in mu(FE) and a 128.4% improvement in I-on, compared to the unannealed devices. These improvements are attributed to the selective improvement of the specific contact resistivity (rho(c)) by the IPL annealing. In addition, positive bias stress (PBS) reliability and temperature-dependent I-V measurements show the improved stability in the IPL-annealed devices and the lower activation energy (E-A) for charge transport, indicating that the channel region would also have a lower defect density and barrier height for carrier transport.